Windows 10 , install limits , beyond the Microsoft (MS) terse statements. (1GHz/1GB)!         

I am doing this not because I want to use  OLD useless PC's no not me, I want to see how far back W10 can go in TIME.
How far back for W10 32bit and 64bit and the answer is NOT the same.
The good news is after many years, after 9 newer versions of W10 , we are at v1909 now. (things work better!)
I am testing the MS, PnP plug in play , servers at MS. 

How old can we go?... The answer is  near 2005!  ( see 4GB limits for RAM DDR)
I define success  a bit different, I do not need the MOBO sound chips to work and are not tested, by me. (same with wifi ) Bit Ethernet worked right in every case.
Why? lose rules by me?, well  that is easy to answer, the answer is I can most or all things born dead, with a $4 USB dongle or some PCIepress card dirt cheap.
$1 (74cents even) Sound dongles,  $4 WiFi dongles. and even far better PCI-express cards, endless sold new and all WHQL certified for W10.( DO IT  NOW !)
For sound the solutions are endless, both headphones, 3.5mm or USB or bluetooth or even DAC USB, dongles, endless choices.

All testing was done with the current MS ISO 1909+ up,, and PCs with current BIOS. (with an  erased fully SSD drive) (I never use HDD to test, they are slow and love to fail smart testing) Please do as you want.
The install limits for 32bit  OS are vastly more easy than the 64bit,  the  64bit  has  strict security features , the NX Bit  feature code must be present for 64bit. (2004 or earlier PCs fail easy)
What I learned fast was if the CPU fails, and upgraded CPU cures the problem (example 1 is CORE2 DUO to A QAUD)
Many laptops 10 years old or near, fail for NX. ! (XD) despite common usagage on Desktops.
On any old PC upgrading the CPU is best, for sure the last mask stepping version. (I will cover that later)
This funny Microsoft statement is are they stuck in the year 2000? with 1GB if ram or OMG 512MB, how silly is that? The truth is the best CPU are October 2004 and newer.
Make your the PC has 4GB of RAM at least, never less. (  3.5/4GB see in 32bit OS is 100% normal)
And a new RTC coin  cell battery. (replaced 1st)
MS SAYS: "1G Hz CPU speed, 1GB Ram,  HDD(SSD) big enough at 32GB is wrong!" 64 is better, 128GB up,are best.
Never let  any SSD go over 1/2 full. (as many PC makers failed to know or learn and some have 32GB drives ouch)

Test conditions:
In all cases the CPU is limited by your chips and what your motherboard , maker allows and BIOS is udated to newest in all cases first.

All tests done with W10 version1903/1909. (not any of the past 8 W10 versions tested by me and many are buggy!  
! NO UEFI junk either! (no safeboot , secure boot and no TPM chips enabled  I boot a MBR SSD only. (less than 2TB sized)
All PCs with CORE2 Duo and quad or CORE i3,i5,i7  can  run W10 .
I test all with no added cards and only 1 USB device a Corsair K55 keyboard (fancy) or old Dell Keyboards.
PCI-e slots empty and with 700watt PSU,(56amps 12vdc or my 62amp PSU, I have 2 PSU, just in case I need to test a power hog GPU card)
This page is mostly about older CPU. LGA775 socketed MoBO's. 
I AM BOTTOM FISHING HERE, devil be danged, speed, or any other issues. (loads W10 and runs W10) Some folks that is all they need or want to do, so here is your answer.
Any PC with relic  VIA or SIS chips onboard or old  AMD Nforce Bridge chips sets below series 600 will fail. (exceptions rare VIA C7 1.2MHz 32bit only, but is a slug at 1GB RAM)

Many? P
C owners do not want o learn or read facts, because  all they want to do is get on facebook?  (DO NOT READ THIS PAGE, hit HOME now)
If upgrading say A CPU is not you bag (ball of wax or floats your boat then don't , but do buy a newer PC,  get a CORE I5 Gen4 or newer and end your pain easy , fast and cheap)

Windows 10 tested: (summary)  (in all cases I have box of CPU's (vast) even lame Celeron's that love to fail (all my chips support NX bit) and LAHF feature (hard to learn) Best is CPU with VT-x featured!
In all cases buy  a newer CPU and for sure the newest STEPPING as seen here.
My test matrix, of bottom fishing a bevy of old PCs. (some custom like Asus or Intel D945, the the others are old problematic OEM Dells. and such.
The myth that G41 chip sets will not run w10 are in fact a lie. (the real tuth is a wrong CPU) Note that even the very old chipset 945 works! May
2005  old. A Core2 Quad or better is best.
PC name or mobo I.D.
OS 32/64
Remarks and  year made.  Most are socket "T" LGA775 PCs (yes old) or AMD AM2+
Dell 790 MT
 series 6 chips sets are still prime, 2011 made.  i3 up work.
Dell 380 (G41 DDR3 pain ) E6300 CPU
Core 2 Duo.
has fussy DDR3  some DDR3 work others do not., CPU picked is highest stepping code.
Dell D520 laptops (attic stored) WOW!
945GM (m=mobile)
32 only
2005 old ! mobile chip sets lack 64bit features ! as see on next PC below a Desktop;.
Intel mobo, D945GCZ  (note #1)  the GPM is best!
Pentium D ,D940
One of the oldest chipsets Microsoft supports 64b (PnP) 2005 made. D800 up CPU is must. Presler.  M3A78-CM AM2+  AMD CPU!
Athlon 64x2 F2+ Both
later I added Phenom II X4 (newest in the AM2+ line) all work but only F2/F3 stepping up in all cases
HP 8540w laptop
i7-820QM Both
My vacation laptop, rugged.  Gen 1 Intel CPU.  2010 PC  The DOD security features are fail, who cares?
Dell 5150c Dimension Desktop  /XPS-200/E510
Pentium D up.?
12/2005 not the laptop Inspiron same model # that fails 64bit.   Some 945G can do CORE 2 DUO !
HP Z600 (dual CPU  has 2 CPU on mobo) C2 mobo
2x X5570 Xeon Both
My favorite old Desktop (owned) a tank but is fast.Circa 2009,   C2 revision of the Intel 5520 chipset.
HP WX4600 workstation
Core 2 DUO +
I tested my cheaper older CPU  QX6850, 2007 to 2010 made. (highest stepping)
Dell 230 Vostro
Core 2 DUO
tested by others. Both in Red means tested by others. Vostro 200 up. All Gens do DUO UP.
D945GPM & Prescott CPU , 5x0J up. 
P4 - HT 520J 32bit only
 Vast old PCs as old as OCT 2004 can run 32bit W10. P4-520J ,530J to 570J (note#1)
D945GPM & Prescott CPU,  651 (first 64bit)
P4  HT 531 up, G1
Both !
  531/551(64Bit only fails) 631/651does both 32/64.  , See note#1   5x0 does not work 64bit. 6x1 is best.

Dell  Optiplex 330
Core2, Quad
Q6700? CPU, GMA3100 GPU. &2009 PC, chipset year Q3'07 (bench'd Q9550)
E0 (QGPK, SLB8V) Q9400  is best deal %
The first test of W10 will the install hard fail... (warning this PC not supported or the other MS lame, trick the installer locks up and no errors)
PCs I installed W10, 2 times (32/64b), and with the Ethernet cable to my fast router and all cases Ethernet hit the deck running! (even that old AMD above)
W10 PnP runs great and the iGPU runs in limp mode and if true, doing and update on that chip , cures the problem.(doing it online, PnP)
No problems at all seen, except the CPU needing newer stepping versions. (in all cases I have top grade CPU like Quad Q9400. NX bit and TX bit working.both. (a $10 CPU)
Check out the P4 Pentium 4 that runs Win10 64bit ! the 6X1 version 651 mine runs great. (newest stepping only, I do not buy older versions ) Mine is SLK9E step "D0" 2006 year.

Many OEM sellers of PC (  HP does!) do not provide a list of QVL memory and worse, no CPU lists (only what they sold new, in many case 2 CPU choices and 2 memory sticks offered)
The best app. to run for 64bit support is this.(tells yes /no)   the best App. to see if free windows COA is in the BIOS see this.<<a  great fact if the 64bit OS runs.
Windows 10-64bit installer just loops in  funny way if it does not like your CPU. (not attaining the Purple screens !) 
( mostly this happens on very old CPUs it gets lost installing)

Note#1- There are many Celerons with no NX bit  dooming W8 or W10 totally. NX bit does show up on P4 G1 stepping. (and many Mobile PCs (vast) this  old do not run w10 period.
These are  the  key factors on CPU choices here,   if 32bit fails so will 64bit...
  • LGA755 socket, (P4 era)
  • Your chipset (Intel 945g and newer is best) and BIOS suports a newer processor. (and in BIOS actual turn on all CPU features (advanced) NX, VT-x and more if present.
  • NX must be present or 32bit support fails.  The 520J is the first 32bit P4 G1 stepping up.. See my 32bit answers here.
  • Last is LAHF support, for 64bit support and learning this is no easy matter, datasheets now GONE. ( gone) (why does intel, not tell what CPU's have working LAHF features?)
  • The best  choice of P4 +64bit support is the 6x1 series of Cedar Mill,  631,641,651 works!,and 661.  (forget 662 and 672 are rare as hens teeth now)  (Cedar Mill is the best P4 !)
Questions and answers on topic , upgrading CPU.

What are the oldest MoBO's that work?
There are over 1000 motherboards that support this CPU 5x0J ( to gain 32bit OS at least) 520J was first.
Why run only 64bit?,(told here
is this great web site). (read about the 64bit Kernal with care)
I Don't know what I  have now?
Answer1 (the CPU lid top exposed answers this, but if not wanting to pull FAN and Heat sinks try this. (the lid top laser marked numbers are here)
What do I have inside now (using only software to look)?
Run Coreinfo. (in cmd.exe prompt box, type coreinfo -f)  see mine here.

Desktops are best, all can have CPU upgrade, (means BIOS current and happy, and chipset correct)
Laptops are a big pain, most laptops old lack the 2 things (NX and TX)  it needs to run w8 , 8.1 or W10 of any version, (but luck happens)

Why not just try W10, first using a spare HDD or SSD if wise,  doing 3 hour load on to HDD is silly today, use  SSD and do  this 30 minutes , a used SSD is only $20 why not own one, even for testing.
Best is to run this and this only if doing P4 work. From cheaper to more expensive, $15 is cost now.... or better. (1 pack of cigarettes in NYC, LOL) this chip runs w7 to w10, ALL.
This below shows my low water mark, or bottom fishing this is the oldest CPU that runs W10,  tested by me. (cost of CPU today $3) D0 is best. I have 651 running. 2006 year CPU running 64bit ! Now that is amazing.

The real truths on W10 istallations are : in order:
  • The BIOS  if not upgraded may not allow W10 at all. (or not supported chips sets covered below) In fact BIOS can go dead, with any new CPU added. (upgrade BIOS first)
  • CPU needs to be Q4, 2004 or newer, with NX bit featured, as seen above last table entry above, 520J or above.
  • The CPU  needs the NX ,LAHF  for 64bit to work many do not and oddly many mobile CPUs did not for years and desktops did.
  • Installing 64bit on PC with max ram of 4GB (3.5GB)   seems  a wasted effort, but if you have some 64bit app that you MUST run , who  am I to tell you otherwise.! and W10 64bit Kernel is VASTLY MORE SECURE !
  • I upgrade to SSD boot drive first and at same time lots of RAM (DDR)  But some folks told me that $20 is too much to spend on screaming fast SSD,  oh well !
  • All PCs need  4GB of RAM at least (shows (3.5GB) with 32bit OS), for sure if you run photo shop, or other memory eating APPS. Many old PC max ram is 4GB (physical) Best is upgraded to CORE i3, gen 1 at least.
  • On more, the BIOS has CPU options, turn them all on, XD/NX ,Vt-x, but do not turn on UEFI or SECURE BOOT. (for sure gaming or old PCs) 
The NX/XD (no execute bit) can have multiple names in a BIOS, including EDB (Execute Disabled Bit), Execute Disabled Memory Protection, EVP (Enhanced Virus Protection), and No Execute Memory Protect.

The oldest CPU that runs 64bit.(my tests)
The P4 HT seen Above, and  The Intel DUO (sure Quad) and AMD Athlon 64 X2, (newer stepping for sure F2+){or  AMD Phenom II last one made!)

Warnings , there are two:
MS ends W7 support Q1, 2020 ( clear as day seen)
Intel ended all W7 support, for drivers end of OCT 2019.  (no more driver ZIP file support from Intel) how that effects MS, now that support ends here, can not be GOOD.
If wise (my opinion) Buy a used PC for 50 bucks and get at least a core i3 up  PC.   (a Dell Opiplex 3020 is cheap used, DIY reburb cheap)

Covering Intel S-Series =Desktop processors; I will not dive into the Laptop CPU rabbit hole ever but did list mine above, in the table.
In all cases of OS installations make sure any kind of HDD/SSD drive found encryption is turned off first and  reversed if found like that... !
Consider turning off UEFI safeboot, secureboot, and fast boot  now done in BIOS if present at all, most legacy PCs have not such thing there)
Never install any OS and forget to run full HDD test first (S.M.A.R.T tests must NOT FAIL)
Then next upgrade BIOS to newers level.
For a more easy install , remove all non boot drives now.  (all 2nd,3rd SATA drives of any kind (HDD/SDD) and any external drives and for sure all USB thumb drives, not  the install W10 Installed thumb drive.
Consider fully erasing any HDD/SDD if you even suspect the drive is not empty for any reasons, or if infected in any way. ( I run killdisk.exe to do that) some OEM disks have hidden partitions that are hard to remove.
I do not recommend doing OS updates (7 to 10), just clean installed, and for sure on any LEGACY PC.
I for sure  have the BIOS upgraded first step, so that it knows newer CPU and new DDR. (and bugs fixed)

Stop reading my page this is only for some folks with super OLD PC's.:
Most folks reading this will find it useless to you with modern PCs, this page is only for LEGACY PC's, and most are problematic due to chips on the PC no longer support,  this is super common.
The PC must have modern Chip, and BIOS that support them all. There are vast chips no longer made (means no software drivers now that work)
In all cases try to force load W7/8 drivers to W10, this can work. (there are no guarantees it must)

I will on this web page show what PCs fail back to year Q4-2004, I only tested back to Pentium 4 Prescott, 520J . (We  are told older is hopeless! and for sure lacking NX bit!)
When I install W10 I answer all things as NO , or skip, I only do Password/name answers. (for sure NO to CorTUNA and no to share devices and the 8 NO's page , no store, no live login's)
I will test many PCs, but first look at what  the installer setup.exe logic does, when run from install media;
Installing to a fully erased HDD /SSD connect to SATA port (0) lowest number port is best. I run killdisk.exe on all disks that are not truly empty. (some seem empty or dead but are NOT)
Setup.exe (logic)"the installer" If the Installer goes MAD (nuts) it goes into this silly boot loop thing with OOBE errors.  (no clear reasons told just gets LOST)
  • Looks at PC maker vendor codes and fails if it does not like some chips (like VIA (some C7 work a tiny bit) or SIS or S3 chips long dead)
  • Turn off all DOD/CIA/NSA enrypting HDD/SSD or the like first.  (your OEM PC maker tells you how to do this the correct way for sure now)
  • Missing boot drive, or not empty or has some illegal fails or partitions on the DRIVE,  or alien boot files, from ApplePC  or Linux , if MS did not format the drive before it will not like it now. (the cure is killdisk above)
  • Then checks if the CPU is compliant at  AMD 64 X2 F2 up  or Intel Core 2 DUO/QUAD  and newer for 64bit (a prime goal that) , about 2005 and newer. if not?, it FAILS.
  • Next is glue logic, if AMD nForce chips sets old then it fails, if Intel Glue  is below series 6 chip sets fail. (Glue = chipset north or south bridges or both)
  • Some iGPU chips like Intel HD2000/3000 ,has no W10 drivers now, but does not actually hard fail, but MS has new magic with MBDA  (and poor resolutions and SLOW !!!).  A  newer Video card added is best now.
  • Then it  checks BIOS for compliance and if UEFI BIOS and fully enabled (disable it?) for secureboot, it may block you . (upgrade  BIOS now , and flash burn the firmware)
  • Checks motherboard for at least one working LAN NIC  chip supported ,be that Ethernet or WiFi. ( the order is CPU, chipset,NIC,sound chips scanned must not be missing or no longer supported by chip maker)
  • The are other key chips that can fail here, like SOUND. (audio) It should tell the installer to find new sound card or dongle. (or let you fix that latter)
  • I just tested 64bit on 1GB of RAM (750MB in fact due to iGPU theft of ram) and  W10-64 bit installed ok,  but is slow at 1full minute to launch CP control panel, yes, slug city. (I have 4GB now after this test)
  • The Installer can get lost (OOBE) for wrong BIOS not supporting your new QUAD or some very old Celeron single core junk. (UPgrade the BIOS first and win)

The truth is, Microsoft (MS) does not manufacture SILICON Chips (I.C's , processors, chipsets  ) of any kind. (maybe badged products?, IDK , like XBOX ?)
That fact means MS must get the  drivers from the OEM PC maker or the CHIP maker! ( and check out the GPU new MBDA magic I call this Limphome mode)
The MBDA may have no proper upper resolution choices and be stuck at 1280 horz. resolution, very limited shading etc. (weak 3D) but does make the PC run and screens do work.(bravo !)

Discounting the MS Xbox, my topic is desktop real PC's ! (and Laptops(or Pad's) can be very very hard to upgrade any OS for sure missing the NX bit!)
See  my dead pool page on why chips go  dead (means support ended long ago in most cases)  see why here too, my Drivers page covers the dead.
The fact is , if the makers are dead, or they ended support at XP or VISTA , there are no drivers for W10. ( dead is dead)
Yes you can try using VISTA drivers in w10, sure you can try that. (and do) but if all old dead drivers are dead for W10 then it is DEAD. (replace the device dead is the only cure)
Cure #2 is buy a used PC, for $50 and buy one  with CORE i3 and higher, CPU based PCs and avoid Laptops if you can. But this rule holds true for both.
Costs nothing to try Microsofts W10,  Zero cost for 30 days !
The ISO download is free to try for 30 days, so there is no reason to not try, really.

Do Fresh installs.
The Best way to make a USB boot media is to pick "BOTH" (32/64/both) as you run the MS stick builder above.( fits on 8GB stick "BOTH" mode selected)
I have run 64 bit on 2005 CPU based PC with no problems , 32bit may go at tad older but I did not test older PCs than 2005 (I have none)

In both cases 32/64,  if your PC has unsupported chips (not bad) but old chips that support for it ended at XP,VISTA or W7, just be aware, nobody can make driver pop out of thin air. (dead support equals no drivers on earth)
In the case of all old CPUs, even the STEPPING code makes a difference for 64bit W10.  (stepping means the CPU DIE mask stepping codes or simply the CPU revision LEVEL, see my F2 codes mentioned on this page.)

Intel plans on dropping , support below this Generation 
(Gen 4 up  Gen3, upgrade only
Intel has already ended support on their older glue logic below chipset ICH7 !

This list only matters if you are playing with very OLD PC's:  The NUTS AND BOLTS OF special instructions in the CPU , missing ( a pure legacy issue most folks want to just forget)
Even old Jan.2010,  I3-350 CORE gen1 CPU can do all this, so is moot this topic if that is you.
Geek-speaks: (the CPU advanced features needed and short answer for each:  (the Intel CORE2 DUO/QUAD runs 64bit W10)
64bit WIN10:    (not a 32bit restriction)
Window 8 64b  needed
PAE, NX, and SSE2
"Your processor needs to support "  ( do not forget to enable some of these in BIOS, NX/XD is one)   Best is to have all these features.  Laptops love to fail for #6 !
This list shows some features that came  before the NX bit at the end of Q4 2004, and most PCs all have lines 1 to 4 already. What matters today is line 6.
  1. 64bit processor (easy, it does or does not have X64 & x86(32bit) both instruction sets)  Back to 2005 year this began.
  2. CMPXCHG16b, Only some early 639/640 pin AMD 64bit processors did not have this. AMD 64-bit processors, before Rev F2 (relic city forget this)  Windows 8.1 mandated this.
  3. PrefetchW, (AMD 3DNOW) again older than 2008 or pre Intel Nehalem processors
  4.  LAHF/SAHF ,  missing on old  or low-end processors predating Nehalem, P4 505 up must be G1 stepping. Old  AMD64 processors also lack this feature. Early Athlon 64 X2 before stepping F2/F3?
  5. PAE ( introduced with Pentium Pro) 1995 (no concern now) Used for over 4GB ram , seen first (@MS)  in XP 64bit.  (almost 2 decades ago)
  6. NX (or XD bit (an NX bit implementation ) "No Execute"  a top security feature !  (AMD =EVP)  Intel Prescott core(Pentium 4) introduction.,Q4-2004 ! (early P4 will fail )
  7. SSE2 -2003?, Windows 8 required this first. (@MS) Introduced with Pentium 4, Xeon, Celeron, Pentium D, Celeron D) Intel Pentium M and Celeron M , and Intel Atom, and newer processors.
  8. TXT  (trusted Execution tech) starting in 2006, most have it but each generation has 1 model missing TXT. May not be required?, I see some folks have i3-2100 with w10-64 lacking TXT and runs ok.
This list above  is overkill  in the year 2019 up, most processors today on your desk or lap, do the first 7 in the list. CORE i3/5/7 all run W10-64b mobile, Desktop or Xeon business class.
In all cases be sure to go into BIOS and see the CPU section and turn on all CPU features LISTED, for sure those above and more. Hypertheading , and more.
In all cases run windows 10 v1903 or newer versions so it can tell you now what is missing , like NX. (is checked 2 ways now, in silicon and if BIOS has it turned off)
Intel history helps.  WIKI words :
In mid-2005, Intel refreshed the Celeron D with Intel 64 and XD Bit (eXecute Disable) enabled. Model numbers increase by 1 over the previous generation (e.g., 330 became 331).
This only applied to LGA 775
Celeron Ds. There are no Socket 478 CPUs with 64-bit or XD Bit capabilities.  The Intel
Core 2 Duo CPU runs w10-64bit  Pentium 4 672 step G1 is best of 500/600 series.
AMD first 64but CPU was in 2006 called the Windsor F2 or latter steppings runs Windows 10 64bit ! My 
AMD Athlon 64 X2 3800+ ADO3800IAA5CU 2.0ghz, sure does
iGPU (GPU on die) began here: first mainstream chips with GPU on-die were Sandy Bridge for Intel and Llano (only for mobile) for AMD.
(a better choice for gamers is  Xeon with no iGPU (making the Xeon more powerful that way ) then add a GPU card.
When you kick the iGPU die section to the curb you gain cores or gain Cache, and speed. Best  CPU is Xeon. 
The Xeons are cheaper used, with flood of decommissioned servers now this CPU is glut status.
(some mobo allow Xeon CPU in the CPU list) I'm not talking new Xeons, just  older PCs and matching older Xeon's In glut status. here is one prime example of that, LGA2011, dual use MOBO @ ASUS Z9PA-U8 (the official list is here!
Intel Xeon E5-2643 v2 (3.5G,130W,L3:25M,6C,HT) for $60 the money you saved pays for the newer GPU card.
Check this out, do your own research to find what mobo have the best flexibility. (by maker and specific motherboards)

Chips can fail new at the makers wafer test plant or final test plant. (Intel or AMD)
This wild acts can make things dead that you would never expect, vast sub models of one CPU  DESIGN, exist  and they do sell chips that failed prime tests for functionality.

Intel and others manufacture most chips with a great dream that all functions and sub functions  of the chip run perfectly and at full speed, but this never happens fully on all Die on the wafer ever. (nor 100% yields.)
This topic is how to under stand why newer chips do not run 64bit  Windows.
If some core(s) or cache ram are tested dead, at final test,  the CHIP is down  graded (like calling it a Celeron) and they sell it. 
Even many other features of the chip can be DEAD (DOA) tripping a down grade and a new name of the CHIP. and sold. (I can promise you there is market for 1/2 dead CPUs. for sure)
See this list of (i7 goal) the oldest core is i3-530 (means Gen.1) and runs 64bit,  JAN 2010 is first CORE what matters to you is if you have older CPU than 2010?
On the older chips, the key instructions can be missing, even 1 missing is doomed from 64bit.

My lab test results, are below to see how old I can go and still run 64bit W10: (boxes here full of PCs , motherboards and CPUs many)

On thing OEM PC's fails to do right is produce a real Spec. (only half hearted and lots of excuses)
They do not tell all major chips used inside and then hide it with that nice  heat sink glued down to key chips,  North /South bridge chips and even GPU chips onboard. Hidden.
The top makers of real gaming motherboards, do this correct the manuals are SUPURB, even did this right from now to 1995 !

 The 2 best choices "legacy PC" are motherboards with all intel chip, CORE2 DUO and newer than 2005.  and AMD 64 x2,  2005 and newer stepping F2 and newer.

 INTEL: (horrors or NOT !) When doing  W10 install LEARN TO connect that RG45 CAT5 port via that $10 cable to your router and omg Plug and Play does work ! (ohhh myyyyy goshhhhh)
The Core2 Duo/Quad and newer, can use better glue logic chips like  ICH7 to 9 and G41 or better X48 all supported by Intel. The Core 2 chip sets stated here.
The problems are all Intel's, that is there chip and they now say unsupported now or this month. (but MS has it here, if you learn to use PnP right or don't know how, here it is in the MS CATALOGS PnP.
There is nothing wrong with the DUO or QUAD CORE2 nor with G41+IHC7 (2009chipset)  , not it can do 8GB of RAM at 1066 clock and USB2, and SATA 3Gb/sec.
but WINDOWS 7 is dead on this chip starting NOW. MS ended it, Jan, 2020.

"October 29th, 2019 Intel officially ends chip sets 900, 3,4,5,6 (that means ICH 7 up are supported)  2004 and back are now gone, no more Intel downloads, (fell off the cliff of the flat earth )
That means  Q65 chip set is now ended as are older,

"End Of Life - (now deleted 2020 link) but here are the words, OCT 2019:
"This download, INF Update Utility - Primarily for Intel® 6, 5, 4, 3, 900 Series Chipsets - Zip Format, will no longer be available after October, 29, 2019 and will not be supported with any additional functional, security, or other updates. All versions are provided as is. Intel recommends that users of INF Update Utility - Primarily for Intel® 6, 5, 4, 3, 900 Series Chipsets - Zip Format uninstall and discontinue use as soon as possible. "
That series 6 rule above is for W7 only drivers going byebye at intel.  (sandybridge) just before Microsoft ends W7. in 2020 Jan. (my guess is PnP drivers at MS will linger for years, despite Intels claim) and does now.(below)
Now see how to use Microsofts PnP servers to see that chipset Q65 works fully in W10,  so this works and does do for AHCI SATA driver but not RST , mode RAID for intel Option RAID setup,  INTEL ENDED THAT.
When Installing W10 make sure BIOS has the SATA port set to AHCI for sure and not RAID, or W10 will fail for lack of intel RST  RAID drivers.
Intel supports that RAID RST only on the most new CHIPSETS. (I like text file version of support seen here)<<< very limiting now. Check this out.

Finding what chips are supported by Microsoft for w10  is a tedious process and I will try old PCs, as 2010 up are cakewalks.
Some PC's that run W10-64bit here are: (graphics excluded, as I have hug box of W10 GPU cards to add)
My HP XW4600 with X38 + ICH9 runs w10 64bit no problems.
Core 2 DUO or the QUAD works E7600 chip 2006 made. 
I put in the oldest CORE2-DUO chip in the XW4600 E4300 and loads W10-64b no problems (using my spare mobo)
My HP Z600 circa 2009 runs 64bit too with no problems.(chipset 36D+ICH10r, with quad core XEON(tm) and 24GB of ECC ram)
Intel chip set 5520 Xeon !
My Wifes HP 8540w (2010) laptop runs 64bit and only the HP fingerprint reader driver fails and not used by us. (the HP security package is 100% DOA and we could care less ,it's for the CIA/DOD/NSA)
My 790 Dell LAB PC runs 64bit  all day long, if I want. Q65 chipset. 
Any Dell 230 Vostro 
(2009yr) will run with G41+ICH7,  The Some Dell 220s run the G45 chip with ICH10 both are supported in MS W10 PnP catalogs.
Any Dell 380 Optiplex G41  (2009yr) runs great but  that lame cross wise custom heat sink, that needs  custom fan + HS -shield  to work.      The Celeron D (is single core and fails w10 but the
Core 2 E6300 runs great)
The 380 runs 4GB DDR3 no problems even did this, with DDR3, mixing 2GB and 1GB sticks(3 sticks) and 1Rx8 and 2Rx8 sticks with zero problems.
I have Dell 3020 and T3610 that run W10-64 bit fast. (these 2 I highly recommend but most of the above are just old PCs retired. 5 years ago.
My best PC is my ASUS z270 Prime.

The Dell G41 logic is very limiting, it does not like 4 or more of my spare DDR3 memories, what gets me in trouble is this MMC logic, Intel list in the G41 data sheet.
1GB sticks (cards)  can  do both 8 chip cards or 16 chip but the 2GB can not, it only works with 16chips,  my DDR3 box full of cards all 2GB fail due to single side and only 8 chips, the mobo just beeps nothing else. see more here.
Now lets go way back in time to 2005
Next up is an old Intel MOBO used and pulled out of and old Gateway PC.  the CHIPSET IS INTEL 945G
945G RUNS:
I have this super old Intel MoBO, called D945GCZ.  4slots of (DDR2-667 best 1GB and never
"Double-sided DIMMs with x16 organization are not supported ", no 2R16 allowed .DS.
The best D945 motherboard is the one ending in GPM , this card has normal FAN mounts, and 4 DDR2 lot)  NO queer fan mounts.
Best RAM is M378T2953CZ3-CE7 (by samsung) have 4GB total.
With 4GB of ram and Pentium D (D940 Presler step code named C1 SL95W ) That was proven to run W8-64 back 5 years ago and now W10 64bit by me. this is the low water mark for 64bit OS. (I found it)
D940 chip works but the Celeron D 336 will not run W10 in any flavor at all. (even 32bit fails due to it  D = Dead 2nd core , wow)
These old  chips sets are 64bit (math-ALU) but not memory controller, addressing it is limited by Intel PAE rules.
4 GB maximum total system memory, and minimum 128MB sticks. Intel still has QVL list for DDR2 and
This old Intel Mobo chip  945G runs video at 1600 x900 resolution, out of  the gate ! Plug and play (PnP) magic.

The worst PCs to own or worst of all buying just a OEM  motherboard only , and using your case , the CPU fan becames impossible. (it half fits hinge mount on mobo but the other end is near impossible to mounts use custom DELL case mounts.
The worst is these old BTX case/mobo , that are what I call MAX PAIN.

VIDEO GPU PROBLEMS:  (mostly folks gaming but if you need better resolution than your GPU can do, with correct drive, then do upgrade, easy and cheap)
In all cases of you don't like the video resolution then buy a new GPU card, (SFF many have no x16 slot so... avoid SFF)
There are 1000 of GPU cards that run on W10, from AMD/ATI and Nvidia. Some even cost $10 used.(ebay deals cheap)

Here are my GPU card choices.

The Big pitfall of CHIPs is below:  The most common causes for W10 to fail to install are here.
The official MS PnP catalog shows W10 Microsoft PnP catalog servers shows support back to Intel Series 3 chipsets  (like G31)
But weak support on many iGPU chips , it will run ok,  but will look ugly 1200 pixels, with the MS limphome GPU driver running, so buy  a cheap $10 video card and end the pain.
Here is my very short and dense fast deadpool list:  (Below 2005 year, is very hard to install W10 at all)
  • Any VIA made chip  or CPU even VIA C7: loads on  32 or dead on 64bit. or any lame SIS chips or S3 GPU dead now.  I lead off here in DOUBLE DEAD.
  • Any Motherboard, (mobo) with any old AMD chips sets , below series 600 nForce, are not supported or below! by AMD.  dead for 32 or 64bit.
  • Any intel chip sets below ICH7 , Intel officially ends W7 chip sets 900, 3,4,5,6 and below   2004 and back are now gone,  dead for 32 or 64bit. But MS supports them back to series 4, W10.
  • Some   900  series up do work  after turning on t he NX bit in BIOS and even upgrading BIOS to max. version)
  • AMD CPU below (k8 series)  and below Athlon 64 X2 (2005) may run 32bit but never 64bit W10.
  • Any AMD based mobo with non AMD glue logic (VIA) (and no Nforce of any kind below series 600)   From 2001- 2007 to AMD nforce 
  • Same goes for Intel, mobo, non intel chipsets (glue) are problematic.
  • The old Pentium 4 (  Prescott 5x0J ) runs 32bit runs only. (Q4 2005 first intel NX bit CPU x86) others made lacking the J code or NX bit missing fail hard.
Here is the minimum AMD CPU list for 64bit installs.

Intel warns you to not run W10 32bit here,  I'd take there advice on newer PCs.

Why have 4 or more cores and good GPU card?: ( as very common question)
To run
  • Photo and video editing apps— Adobe Photoshop, Adobe Premier, iMovie
  • 3D modeling and rendering programs — AutoCAD, Solidworks
  • Graphics-intensive games —AAA+ $60 games, 3D, run better. (playing Solitare/Hearts/Spades is not gaming , sorry)
  • Scientific simulation software — MATLAB
  • Demanding productivity apps — Excel
  • Engineering tools , CAD/CAM or CAE.

My GOAL was to test the most common old Chip sets  from 2004 to 2010. (newer just work great newer than Core 2.)
LGA-755 Core2 chip sets  (Q43/45 are best DDR2) (Keep in mind that Intel and or Microsoft can or will end support for old chipsets at ANY TIME)
I did test the old 2004, Pentium 4 Prescott HT 520J CPU on the 945G board. (this I  believe is the first CPU by intel that runs W10)
This list shows chipsets and Core2  The G31 up are best supported at MS.  (blue links below show the MS catalog matchs (supported proof))
See all chipsets in nice wiki brief here:
These are chip sets that might work:  the Ones in Blue links below all run W10-64b no problems.
Lakeport: 945PL /945P / 945G / 945GC / 945GZ /  / 946PL / 946GZ {2005 era, Pentium 4, Pentium D, Celeron D, Core 2 Duo}  The G code and Q means iGPU on die,  P code none.  (645G runs Pentium D940 but not D800s or lower)
Broadwater:  i946 / 946GZ  / P965 / i975 / Q965 / P965 / G965 / Q963 / i975X  { 965 ends  pentium 4/D and adds  Pentium Dual-Core, Core 2 Quad, Core 2 Duo, june 2006}
Best is start here:
Bearlake:   P31/G31/G33   / P35 /Q35 / G35 / P33 / Q35 /  { Pentium Dual-Core, Core 2 Duo, Core 2 Quad .era June 2007)

Eaglelake:   G41 /B43 / P43 / P45 / G43/ G45 /  Q43 / Q45 /     (Core 2 Duo, Core 2 Quad   June 2008 ) The Q45 is the cream de la creme this era,. for Core2. 775 socket , Q45 has  Intel VT-d

Intel  drops W7 support oct.29th ,2019 (A Halloween treat to the world, no more support even for a 2010/11 PC !) The are deleting the W7 driver zip file soon at
W7 support ends at Intel at series 5 back.Q57 2010 and back. LGA1156  and back. Series 6, say H6 and newer is supported and is LGA1155 Sandy Bridge.

My logged Journals is below of testing many motherboards old, ones that have change to work, ones lacking dead chip set makers by SIS or VIA.
In every case Ethernet hit the street running, (GPU's not to much)

My Example section is here, beside OEM lists above, first is DIY real PCs, W10 64bit is GOAL and SUCCESS : (tested with 4 processors,  the oldest DUO to my newest QUAD Phenom-II-x4)

Here is my old PC with mobo M3A78, and the huge CPU list. ( I is a spare PCs I store in my attic or for doing dangerous tests)
I am testing it with 4 AMD CPU's the  oldest  allowed (F2) , and newest and mid range  age.  F2 G1 and G3 stepping's. (and last the newest PHENOM II, 955 x4)
  (2008 MOBO with  2005 to 2009 (Athlon 64x2 F2 stepping, to Phenom II X4)
The exception on AMD is:
For AMD CPU motherboard, the Asus M3A78-CM  AM2+ socket,, this great 2008 mobo 780v based, AMD supports w10 64bit (here) but so does MS  too here.
The real beauty of this mobo is no antique series nForce 400 chips there have XERO support today, but 700 series does.
CHIPSET 780V/SB700/ RS780C for sure  Runs W10-64bit, with no problems at all, It even installs with only 1GB for ram  as I removed 3 sticks of DDR just to prove it works. (a real slug this is but does work)
In fact only 750MB or Ram was there , the rest is stolen by the iGPU intel thief ! LOL !  A good video card ends this RAM theft.
 Proof  of W10-64bit running here. (Athlon II X2 245 step:DA-C2  @ also G2 runs then F2 (oldes) runs same and last my Core2 Phenom II X4 955 quad, sorry  x6 still costs $40 or more so not buying one ever,
No number 939 (s1) socket CPU fits here, only AM2+ up CPU. (x2 has 96 processor choices sold,  the first 939 sockets are useless now) AM3 is mostly about DDR3 RAM usage. Mine is DDR3. 6GB now  loaded.
Yes GPU 780v ( shows up as RV610 and as Radeon3100)  is stuck in MS limphome MDBA mode, 1280 pixels wide, but works. Just slow and 3D is a slug, 1 FPS?

The installed  Max Resolution pf  780 chip, is limited, to 1280x1024 only in windows Microsoft Basic Display Adapter. (MBDA)
If you don't like MBDA performance ,  (load the W7 driver that does work right, from and loaded to W10 with no problems.
The Rv610  iGPU chip  in W7 (correct drive), 2560x1600@60Hz.  but here is no W10 driver but the W7 Driver does load to W10 with no problems and full performance.
On trick to do that is load the W7 driver for the RV610 using old W7 driver, and force install it, using Device manager or using clicked setup.exe and   (luck happens so do it)

There are 4 ways to force a wrong driver, using W10 compatibility mode, and force the setup.exe , force the extracted, MSI or use update, inf file.  One can work , we just try all 3 ways.
The 4 ways are:
  • Use device manager, and right click the GPU chip device and pick update driver, and browse, and then navigate to the setup file in this case (windows 7)
  • Run the setup.exe see it fail then right click the setup.exe from Asus , Right click Properties + compatible mode,  to W7. The run it. (if fail?, mine did not)
  • Extract the whole, video driver package from Asus in to a folder, and run MSI files that may be there.
  • The same as above but the extracted files has folders and some are 64bit and you see bunch if INF file, I then try to load the one  that matches my GPU.

The W10 to W7 forced compatibility mode works perfectly on the setup.exe. (runs Catalyst v3) with no errors at all, (I now get 1600 x 900 resolution) just doing that. (the driver was at
The Passmark scores are :2D  =  296@10% and 3D: = 3FPSa nd  score 56 @8% sure slug but 3 times faster than MS< MDBA driver.  (my driver is here, as 1 example.)  (math?, 3x faster slug = still a slug)
Still stumped, then:
Or buy newer GPU card. (like this cheap but pretty fast GTX570) (or GTX480)
Some old double wide cards are huge, and 11.5" long so only real Desktop case fit. and 2 AUX cables just for the card, the card is Super long.
 (never buy a CARD and not check your PC for Height, Depth and Length. (allowed inside) always read the card makers full spec, and only from true maker, some cards have 3 fans and are super long and hit drive cages, many folks remove the cage.(or DVD drive or things they don't need to make room for the new card.
Then use a ruler and measure your space inside the PC, if your PC is 10" long in X16 slot the 11 inch  card is no good.
Learn that there are 10 makers of cards, and many have 10 or more models of just one card and all 10 models even with number 1050 have SUB models. , are not the same SIZE !!!
Sub models can have different speeds, different heat expelled (needs more fans) and more RAM. (lots and lots of submodels exit and for sure prices)

I always put in a new SSD (128GB at least) as soon as you do that the PC  comes alive ! Mouse clicks are no longer 30seconds long they are now 1 second long,  30 times faster human  GUI  experiences.
Next is my zero buck SSD caddy, (have boxes of floopy drives in my attic room) This is in my Phenom PC.
SSD have no motor no vibrate nor have weak , G-force ratings. 1500 G rating is crazy high on SSD. (Samsung , 1,500G & 0.5ms (Half sine)) so mount it any way you want, even tied to front of CASE.
I like keeping banks of HDD present, (old and good) Drive E, F,G: (HDD 1, 2) HDD0 is SSD.  Then hide the SSD like this, done this I have on may PCs and even servers. Below is an old $20 used SSD, that I like.
I also do this to SLIM DVD drives gutted. (where the owner has no use of any DVD now)

M3 DONE ! Runs 64bit like charm. (and light gaming with GTX570, say running game CS counter strike)

Video card choices are huge 1000's are supported ! for Windows 10 ATI or Nvidia.
Here is my all cards made page for  W10 GPU support, it is very simple choice.

If you hate your iGPU or old slug like GPU, well try a better one.

Even simple cards like a 2007  $10 used card works.

or the  (like this cheap but fast GTX570) (light gaming sure) Run Counter Strike?  (best bang for the buck I say)
If gaming only you know what FPS you will need, and I bet it will not be a 2005 PC or card, of any kind. (this page I'm doing here is for old PC)

If all you do on a  desktop , is  simple  reading email, reading web pages, using MS WORD or Office tools.(Notepad, or play Solitare) Any PC can do that, any card, even an $8 card.
Watch out for GPU Cards that do not do movies well. (or you need for DirectX 11 or 12)
Any cheap Video card will work in what is called the 2D mode. (even a $8 card sold on fleabay works great even 10 or more years old)
But if you want to find a better card (ignore prices in this list) go shopping,  even on Fleabay, for used cards.
I made this list for the best Nvidia cards The prices are and were silly to post or log, ever, so ignore them,. Best is a used card and bid.(bang for buck rules) I have GTX1650 now !
Do not buy cards dirct from China or you will get a COUNTERFEIT fake card,   (spend $50 get a used old $5 card you will and wrong model, these jackasses there, hack the VBIOS to LIE)

The list is here best one:
Run the megaList.(next)

In the name box type , Radeon.
The click 3D tab icon for fastest to slowest cards.
The RX-580 looks real good. (bang for the buck) (gamers want max FPS for the buck)
I think RX means R(10) generation 10 cards, marked as RX. (but I'm no RADEON fan boy)

Warning some brand new rare cards will not allow booting an OLDer PC,  just some brands. (this is UEFI HELL)
Some Newer OEM PCs 2020  the GPU card is married to the UEFI and worse far worse, only the OEM's cards can be used, $$$$$,  so avoid OEM PCs' build our  own DIY, using say a  Z270 prime.
Each maker has like 10 choices for one base numbered  card (say 1050 models) Different : (ram, fan counts, length and height and speed grades) the cure for probles is simple  change brands.

iGPU? Integrated  GPU found inside all CORE i3,i5 or i7 CPU. (most if not all are no good for real gaming)

Basically, Intel Graphics (iGPU) problems , the  HD 4200 (read rule 6  but is W7 limit at Intel not MS !)
Also known as onboard GPU as done on vast PCs in 2009,  like my M3A78 card does. (or the CORE2 or AM2 CPU did) (onboard means on main board called motherboard)
W10 even 64bit installed easy on any of these now but is stuck  what I call LIMPHOME mode.  MS calls that  MBDA (a very great feature this, no BLACK screens of death like in the olden days)
Intel dropped the HD 2000 and 3000 iGPU (2011 CPU !!!)  Microsoft keeps it  from being 100% dead with MBDA. 
But wait the OS installed ok , and only the resolution is limited !, (and shading etc) but runs great for desktop usage.. Looks ok for just desktop work. But may fail watching sreaming videos of any kind any where.
The cure as always simple buy a new GPU card and install it.
The newest driver page at Intel for HD Graphics engines are here.

DEAD IS DEAD, and means, gone forever, the product and new drivers for any new OS.
Here is a list of baseline dead chip makers.

Here is my page on the same topic "dead".     The list grows every day.

How to know if W10 will run on my PC.?
  1. IT IS  free to try for 30 days, so go in to your closet, of your spares shelf  and get a used good $20 SDD 128GB (best size/price), then get it erased is the best way to do this)  The SSD speeds up the process and more.
  2. Remove your PCs HDD (or pull the data cable), and put in the above test SDD erased first and not failing S.M.A.R.T TESTS. 
  3. Connect the router in your home to the PC with a CAT5 Ethernet cable works best . (plug and play needs to work for best results and for sure older PCs.)
  4. Insert the W10 install media. (USB boot stick memory device)  The W10 ISO comes on 3 flavors, 32bit , 64bit and both, pick this first. 
  5. I have 2005 PC with W10-32bit running and is fast 4GB ram.(max) (A Dell D520 Core Duo T2300E)
  6. Boot the media and fresh load the old SDD with W10 , do not forget to remove the  USB stick when told to!
  7. If the W10 does not like that old Intel CPU based  iGPU HD 2000/3000 sub-chip then install any modern 15 years or less GPU card. Bingo works.
  8. See now what works and what does not.?  (is this hard?, no it is not.)
  9. If any feature (device) is dead, or shows errors in device manager? go to your OEM web site, and get the newest driver from them first. (above Plug&Play failed)
  10. If the OEM (say PC is HP/Dell) fails  (PnP fails, get it from OEM, if OEM fails get it from chip maker if still exists at all or even supports W10 at all. See DRIVERS HERE.
  11. Do not get drivers from Russia /IRAN or from driver scalpers or malware sites, if Firefox v69+ says the site bad it is, same with dead certificate web site, RUN AWAY From there. (sad I have to say this at all)
  12. Run on all drivers downloaded, first. I never skip this test, on small apps and drivers for sure.
  13. The chipset w10 is here and is safe, but if  you read this , they tell you some things your OEM added will be dead with this driver, Intel did not make your PC, ok? AGP is now dead, as 1 example.
  • Order matters, and first is PnP let Plug and play do its job even while installing W10.  This is the Microsoft way using qualified drivers.
  • Next is your OEM drivers, at Dell, or HP or Acer, or whom ever. Go there and get your drivers. (if missing there as most PCs old are the do the next step)
  • Find out which device is dead or has missing driver, use device manager, then go to the makers web site and get it. I have no covered all 3 ways to get a drive and not let you get infected.

A Crude diagram of the old 2005 processors that can run W10-64bit.  If the 2nd core side is dead in anyway Intel might call it  a Celeron  so avoid those
Watch out of mobile PC's as many have dead NX bit and is not fund in below Desktop CPU's (sorry)
AMD  KUMA 'B3' series chips are NO GOOD at all,; 1 DEAD CORE)
AMD 64 X2 (series ran for 10 years, 2005 to 2010)  All Phenom chips are better in all series. The fastest chip in this era before FX-nnnn series (to be found in wild) is AMD Phenom II X6 1100T Black Edition (rare as hens teeth)
AMD later dropped the 64 stamp and just called it  the X2 then later, they went to a far better Athlon II chips.(all CPU are now 64bit,  so no need to stamp it 64) Or the better Phenom chips. (X4 is real good)
Anything Athlon II  / old Athlons AM2 and any AM2 series chips, Phenom too.
AMD newer stepping G3 and G2 version work as does the most old called AM2 F2 versions , or any newer versions 2005 up and any steppings, equal to F2 and higher.
Any vastly newer  Athlon II chip work this is GEN 2 chip is seen in 2009.

This section here is my wayback machine, to see just how old a CPU you can run.
The fact is many features are not shown here, these are basics.  The NX bit is very manditory and can be missing,  939 sockets are fail and so are many mobile chips.
This is the base underpinnings of  a working 64bit OS.  (intel DUO  left side  and X2 right) or newer. (or  AMD quads )

Here is Core2 in more details,  no drawing exist for all details, for sure.

AMD Windsor is the best name and version or newer.  May 23, 2006 first release. or F2/F3 or G1/G2 Brisbane only.

Sockets matter first. (if it won't plug in why wonder? In cases luck up your chip in the wiki and see if it has NX option, I must. Below are only some I tested out of 600 variants.
Most Desktop l AM2 socketed X2 work from first steppings F2 stepping (my goal is to make sure  F2 works and it did)
I tested F2 to G3 steppings on up even  QUAD, and all function perfectly. ONLY AM2 sockets work never the very old 939s1 socket. (< non AM2 and non AM3 up.)
Windsor AM2 and newer, May 2006 and newer only. (never stepping B3 or E4 or E6 , as they will fail)
Real photos speak volumes see that stepping code,! alway look up what YOUR stepping can do., inside your PC or on a new CPU.(or while shopping for one)
NEDHF = BH-F2 stepping,  this is  1 of may CPU's I have AMD.    old and one super new Athlon II

Core 2 DUO; July 2007 ,  E4500 model. SLA96 step.    I think all CORE 2s work as will QUADs  The below works, and is one of the oldest working CORE2,  that run w10. (my low water mark)

One of the best old AMD processors is 2009 made Phenom II (mark2) and X4 or X6,
The X4 can be had for <$25 today Below is X4  3.2GHZ ! ( just before FX CPU came out) 
This X4 Phenom is FAST ! Passmarked at 1876 (10%)slow by today standards. (lots of RAM and SSD it is fast)  This is the oldest CPU I would ever consider. The Phenom!

OMG, real INTEL PENTIUM's? (the name that lasted forever and keeps on giving, not?) The Magic  Intel  year is  2006
We do know that the Q4-2004 Pentium 4 HT (520J) runs W10 32bit. (I have one too) but lets talk 64bit.
Keep in mind just the motherboard alone (chipset or BIOS) can block you for 64bit or even 32bit.
What wins here are 2 cores.  D mean DUAL.
The OLD chip the Pentium D 900 series does run 64bit, if LUCKY (means BIOS not brain dead or too old) a circa 2005 to 2008 CPU. versions and first ones are dead 64bit. The 800 series are no good.
The wiki is amazing 2 lines below tells you all you need to know.  SEE XD? (means NX too)
Q1:2006 released to world:  (shows first NX version below)
"Presler also included Intel VT-x (formerly Vanderpool) – although this was limited to the 9x0 models, and not in the 9x5 models– Intel 64, XD bit, and EIST (Enhanced Intel SpeedStep Technology). Presler was released in the first quarter of 2006 with a 2x2 MB Level 2 cache. Its models included 915, 920, 925, 930, 935, 940, 945, 950 and 960 (with a respective 2.8, 2.8, 3.0, 3,0, 3.2, 3.2, 3.4, 3.4, and 3.6 GHz clock frequency). "

Steppings that work are for Presler: are:  (the older the CPU the more steppings MATTER !!!) The SLxxx is on the top of the chip.
C1 (SL9DA) (bingo below) 2006?
D0 (SL9KB) (newer it is)

The  Pentium D brand was succeeded on July 27, 2006 by the far far better Core 2 (is basically it is just two  P4 dies,(cpu) side by side)

ON THE WILD SIDE? 64bit support W10 is the running goal. 

The wiki on Pentium 4 MOBILE shows not one chip supports NX bit. (so if you a laptop don't  expect any P4 to run W10-64)

Some Pentium 4 can run W10, but there are 266 versions of P4,  P4 (Pentium 4)  Below is the 631 HT. newest D0 stepping.
Only the newest versions of the  P4 run 64bit W10
Or simply upgrade your CPU, only the OEM maker of the PC can tell you which newer CPU they support (in BIOS and the soldered down chip sets (G31 up)) If the CPU is soldered down too, well no possible upgrade here.

The P4 Williamette has no NX ,Same with Norwood, and the first Prescott then . and then..NX.. this happened.
The Prescott 2M happened. In Feb. 2005 and NX is born in the P4 Q4-2004 (520J). (but not on any era same  mobile processors! , my joke is the NX bit drains the battery faster? meh!  )
The best place to see what a CPU's can do or not do is here. CPU world, for sure on Stepping variant oddities.

Cedar Mill ! All models support: MMX, SSE, SSE2, SSE3, Hyper-Threading, Intel 64, XD bit (an NX bit implementation)  Jan.2006 released newer and better than Prescott
The last 2 steppings C1 and D0 have SPEEDstep.! feature.! GET THAT !

MY P4 HT 520J below: Runs W10 32bit.  Has NX bit , first one too (x86) Q4, 2004 released. (tested in my 945G rig)

Old PCs have this 4GB limit (3500MB,3.5GB limit ) 32bit or  via PAE addressing mess. Later  this all changed with CORE HASWELL CPU DIE.
We all know that 32Bit CPU can not do over 4GB memory (2 to nth power (2 nth 32). (Take your  Ti-30x  calculator click 2, then click Y(x) then click 32, and last press =) if no calculator use tables.
But 32bit CPU may be limited to 2GB for system and 2 for RAM. (per this set of complex rules)
With PAE you gain up to 36bit INDIRECT addressing per these complex rules. 64GB max.(in theory)
Next is the so called first 64bit CPU that are in fact 64bit CPU for sure , but many old mother boards use chipsets that only do 36bit addressing. (using PAE paging hacks)
and last is the  true modern 64bit data and DIRECT 64bit addressing CPU , (real and true 64bit addressing and super complex legacy support "intel inside")

3/4's of  a GIGabyte wasted DRAM. (most is used as VRAM by the iGPU)

The New PCs now have adaptive, memory mapping for LEGACY hardware or NO Legacy hardware (PCI, etc) (see map)
Legacy support is still present and even  for ISA/Parallel printer ports, if you can imagine that. (even a second MonoChrome video card, allowed, wow ! (vol2,page25 Intel data sheet I3 gen4)
Notice the word RECLAIM used, or remapped or adaptive. ! (all this new logic prevents wasting DDR RAM (DRAM)
Modern Memory MAP: (anything but simple)

Now my GEN7, vary little wasted DRAM.

W10 32 bit limits (fresh installer limits   to say any SSD not some old dead slow and bad HDD 2 decades old.) (life is too short for SPINNING RUST Drive, called HDD)
The installer will act dumb if you go too old of PC or CPU, it will do this silly MS OOBE dance, it never allows you to setup and users account and loops this silly OOBE errors thing.
That THING means MS does not like your chips. (last seen be me with PC with 1 core CPU Celeron or failed for QUAD core due to me not upgrading BIOS first)
If stuck in OOBE,stop.?
Some times the intstaller posts vastly more clear errors. (specific)
Step one make sure you PC has NX bit CPU installed. Run Coreinfo. (in cmd.exe prompt box, type coreinfo -f)  see mine here.
Next is to turn on all CPU options in the BIOS, and run the newest BIOS (upgrade this first)
Still failed? (make sure chipset it 945G or newer (sorry 915 is a fail)
Last chances?  (chips./cards or devices all mean the same thing) You pull them or disable them in BIOS. (USB devices, just pull it)
The best tactics now is to remove or disabled in BIOS, the LAN/Wifi cards or devices, and any not needed chips , wifi and Ethernet , and SOUND (audio chips) Bluetooth if persent (rare to find in 2005 or older)
The contrary action to that is if the local iGPU engine in your chipset is not supported, then install a GPU card that IS. !
Many PCs this old have zero support for WDDM drivers , forward, but do try to load W7 or W8 drivers if found WDDM drivers (for GPU chips) (some old Vista WDDM1 drivers can work but it pure LUCK)
W10 does not support older XDDM drivers for GPU. (Displays)  in fact ended at W8. (there is no XP driver support forward to W10) XDDM is now dead.
One best trick of all , for sure DESKTOPS is put in a WDDM supported GPU card, one with at least say W8 drivers support and shut off the iGPU in BIOS under iGPU, disabled or with Dell set to AUTO mode. (igpu ,PCIe, auto)
Windows 10 32bit does load to PCs as old as Pentium 4 HT 520J . (2004)
Many ATOM CPU were supported then later dropped, why use any thing with any ATOM, I say? 
Laptops with CPU soldered down can not be upgraded,(noobs ask) and a better mobo (motherboard) is not sold. (Toshiba horrors?)

Here is a nice page showing at the bottom of the page the very old Pentium 4's that do NX bit. (a.k.a. XD feature, or NO execute bit)
AMD maker calls this Enhanced Virus Protection (EVP) = NX.
Try to know at there are vast CPU's made and with different mask steppings (read versions) that may not run W10 ever. (2004 year and older mostly!)
In addition to that , know that your BIOS may not support NX or  is simply turned off (upgrade the BIOS first). In fact some lame toy grade PCs made the BIOS has no settings at all, of  any usefullness here. (lame they are)
The PAE features must be present too in the CPU , this is 36 bit indirect memory address, you must have. W10 will run on 1GB (super slow but does very well on 4GB (minus reserved 500 MB)
The installer does not support every chip ever made, if the the chip driver is 15 years old and does not work now, with W10 , the chip maker (and their driver) are EOL, end of life, forget it.
All things have and end so forget things that are dead. (sure  try loadeing the wrong driver, sure....if you have lots of free time, to waste sure)
The PC is old 1.5 Decades old, and has value of about $10 now, endless motherboards this old and working see for $10. (gee a vastly nicer Dell 3020 is only $50)
If you are wise and have a real DESKTOP and you disable the GPU (called onboard) and then installed  good  newer GPU PCI-express card,  the PC may run W10. (very strong changes, not CPU limited)
OMG even a $10 GPU card works like 8400GS? ( 1pack of cigs, stop smoking?)
If the CPU fails? wow,did you know I just upgraded a Sempron PC to Phenom II (64bit) and runs W10 64bit now (and 32bit works too?) this CPU cost me a whopping $10  1 pack of cigarettes in NYC. (ex GI jokes sorry)
The NX requirement is wise and correct by MS !, not just for the vastly better security, but the fact that most PCs that old lacking the NX bit have hardware that is no LONGER supported by the maker (no DRIVERS)
That fact above means MS Microsoft can not just poop a driver or pull one out of their  can.  (in fact if you really looked most makers of chips are GONE now, or left the building or are merged and zero support ! )

AMD aside,  Intel introduced the XD bit feature in x86 processors beginning with the Pentium 4 (Q4-2004) processors based on later iterations of the Prescott core (read that line carefully , LATER word (that means steppings too)
Prescott was born on On February 1, 2004 ,but only the later ones work Q4 520J (J UP)
Now the Prescott secret told at wiki. (they nail this in one line)
"The 5x0J series (and its low-end equivalent, the 5x5J and 5x9J series) introduced the XD bit a.k.a. eXecute Disabled bit"
That means it must end in "J" or will not work.(just the first chips made that date ) (or newer, there is always newer and better CPU's)
later Chips better ...
The best upgrade (2004 PC)  would be the HT processors ! Hyper treading is prime.  NX is MUST.
This is the bottom of the pit here, 32bit HW support is ending fast world wide. (no new PCs have it  , no new intel chips support it, (cpu nor chipsets)  32bit is doomed (not applications ,just hardward limited )

Use this great resource to find an old CPU that runs XD and even better HT.  Upgrade the CPU. (if the PC maker allows it)  You can't do what BIOS will not let you do, unless hacking BIOS. ( Why not buy PC 2010 or newer , why not?)
In all cases why not just try it? It costs nothing to try, the ISO from MS is free to try for 30 days. (a wise choice by MS if ever)

Laptops are a PAIN, ALL WITH soldered down GPU and CPU are double pain, if you can't upgrade either and you must to gain W10 your lame laptop is doomed. My HP8540w is best, 2 sockets ! (runs 64bit !)
The newer laptops that are thin, CPU sockets were not used, to gain thin, so you loose there.! and no DVD drive, and only DP port on the side (thin too).
Dell Inspiron 17-nnnn
HP Elitebook 2530p
Worse yet, the Laptop with CPU sockets 478 they are callled, can only run lame mobile CPU chips and not the far better 775 desktops CPU !

Core 2 focus points, DUO and Quad, which CPU are best?  LGA755 only. (only covering newest of this generation here, 2008 and 2011 for QUAD.  YMMV your mobo may vary (motherboard = MoBo slang)

Well that is easy, the newest highest stepping is best, here are the details, found deep on the DARK web,  intel shut down PDF in 2018 for all CORE2 documents. (of value) { and learned has them squirrled away too, cool}
I did not test all steppings of all CPU (a crazy idea that), nor does your OEM or the MOBO maker nor did, Microsoft, or intel, but I did find some very old steppings that did work above. (2006- E4500 )
Exclusive of OEM mobo restrictions of BIOS or does not support this processor or bandwidth limits or clocking limits, what might work is listed below:

The first big problem is called TPD watts,  if you motherboard VRM cn not go above 65 watts that is the limit, but if it can do 95watts, only the heat sink may need to be changed for the newer 95watt chip.
For those curious TPD is hit when you GAME (AAA+$60+ Games) This is wasted heat to go fast , and you burn more heat clocking any CMOS device.  (many OEM fail to even disclose VRM limits, like does for 25 years)
VRM = Voltage regulator moduels (with current limits too !) Overheating it would be a DUMB idea.(includes all chip too)
The Core 2 DUO has an book called "Specifications UPdate" (PDF) (now missing at but is here and here ) I have both now, quad and duo. (took me big work to learn this fact)
The book shows all errors, called errata , CPU BUGS actual (as many as 75( is what they are, (logic errors cured or not) and most important is the pages show what you get per die revisions.  (including new FEATURES)
The highest revision is best, and also UPDATES IN FEATURES ) this list proves to you that features are added at die revisions, like Execute Disable Bit (XD) or LAHF and best of all VT-x , buy only CPU with code 4 below.(IMO)
DUO choices best. are at the end !

Last is  my QUAD list. Most  older  2008/9 MoBo  may do the QUAD if yes, DO SO !

If your Mobo can do 95watts (VRM and CPU heatsink both) then run code 19.  Most mobo can not do , extreme CPU. above.
You will find most of  these CPU dirt cheap now. The Q9550 is one of the best.(S or no S suffix) stepping E0

CPU upgrade rules are simple:?
  1. The socket is first, fits does it? LGA755 for 755? (you can not skip , add or cut off pins)
  2. The Mobo supports it. (now that is complex) and top makers like like my z270prime have  QVL CPU list. (a good reason to buy from them for SURE)
  3. The upgraded BIOS supports it.
  4. You pick the newest stepping and the best CPU in the class supported. (if CORE 2 DUO now get CORE 2 QUAD if allowed)
  5. The CHIPset must support your choice. (both the north or south bridge chips)
  6. and the maker of you mobo supports you and the mobo.(now or did) (new BIOS for sure at the least)
  7. The MoBo VRM supports your CPU wattage (TPD) 95 watts is a common limit but really is #2 above. VRM = CPU voltage regulator modules.
If confused?, do step 1 , buy a CPU used even for $3 whole dollars and try it,  be brave. (no harm will come) even have FUN!

Version 10.  9-9-2018 (first) W10 only,
Revised 10-29-2019 (added MS chip set driver link, to PnP servers as a demo)