So I have 2 complete systems that are currently spare.

System 1 has a i7 3770k with 8GB of Ram and a GTX 960
System 2 has a i5 3570k with 8GB and a HD7770

I watched a couple of YouTube videos from Philcomputerlab which has given me inspiration to use one of the PCs above as a WIndows XP Retro PC. I am a bit conflicted however as the only game I can think of that benefits from XP would be the original Far Cry. I am really considering using Windows 7 instead, one thing I am set on is using an x86 version.

I guess my question is, objectively speaking, should I use XP or 7?

Depending on the hard drive size you could do a drive partition and have both XP and 7 loaded then use a boot loader to switch between them. This would come in handy with programs that have issue in Win7 but are fine in XP.

By "x86 version" I assume you mean 32-bit? If so, you'll only have access to 4GB RAM. I'd go W7 purely for the option of 64-bit = you can actually use all 8GB RAM, not to mention you won't need to reinstall your OS if you find a DirectX10-11 game you want to play. (Even DX10 is now 13 years old, only 2 years younger than Far Cry 1).

Edit: As for dual-booting, if it's just for one single game (Far Cry), you may be better off tweaking it. Eg, Vista and later broke water reflections, and yet "SilentPatch" restores them again as well as fixing the crashes, broken VSync, etc:-
https://www.pcgamingwiki.com/wiki/Far_Cry
https://cookieplmonster.github.io/mods/far-cry/
https://www.wsgf.org/dr/far-cry

Do note, with 32 bit os you won't have access to more than 4GB (perhaps only 3.7GB available, rest is used by the hardware). You would essentially waste "computer power" by going with XP or Win7 32 bit. Might also have trouble finding drivers to XP for some hardware, especially 64 bit.

Also, there is 64 bit binaries to Far Cry.

If you go with dual boot, best of both worlds, remember to use MBR not GPT, and install XP first then win 7 (XP 32bit + Win 7 64 bit).

Is there any reason why not just use the latest windows?

I would also go that extra mile, even parsec, in order to be able to play Far Cry so I understand so well :-) The game works on modern systems except SOME Nvidia driver versions are bad. It seems that there is one setting that has not worked for many years now but as long as you lower that you could play.

Pretty decent systems both but that AMD HD7770 is totally dated by now. Does not matter for such old games though.

My thoughts exactly. What do you hope to gain from running an old OS? You won’t get support, may find many issues, and have a lesser experience overall. The only valid reason I could think of is compatibility, but as yet,I have not found much that will not run in win10, and there will be a lot which won’t run on win xp.
For instance, are there win xp drivers for a gtx960?

Thanks everyone.

Just to clarify a couple of points some of you have raised.

I was intending to use 32bit WIndows for compatability reasons, for example, 16bit application support. I intended to remove a 4gb stick as I knew it would be wasted. As for the Far Cry fix, I didn't know that existed! I will definitely check that out, thank you for that!

Don't get me wrong I'd happily use Windows 10 but there are some old games that I like to play that I can't due to incompatability issues. As an example, one of my favourite games is Dark Forces 2 - Jedi Knight, Under Windows 10 I am unable to enable 3D Acceleration - I am forced to use software mode.

If you guys see that I am missing a trick here then please let me know :)

The idea of dual boot is a good one though so I will very likely do that.

Sounds good. 32bit games with 16bit installers are so annoying. Many of those you could install on a 32bit system then transfer to your daily computer. Occasionally tricky in Windows what with registry keys and small files saved all over the place. Some drm also do not work on modern Windows.

Like others have indicated, your "retro"-PCs might have too new hardware for Windows XP, ie. you might not find working XP drivers for them (e.g. the graphics card etc.).

I have a couple of Windows XP retro-PCs myself, but they are much much older hardware than yours, e.g. ATI Radeon X800 Pro graphics card etc. My retro-PCs are from the era when XP (and possibly even Windows 98SE) were still a thing. I am actually running also Windows 98SE on them, dual-booting.

If you mean to make those two PCs retro-gaming PCs, I'd probably install Windows 7 on them. Maybe dual-boot it with Linux too (who knows, maybe you can make some old Windows games run great also on Linux WINE). Have you tried ddwrapper, dgVoodoo2 or such utilities with the game? They seem to quite often help in such cases where the game is expecting older graphics cards than what you have, or older DirectX/Direct3D. At least they helped me with e.g. Might&Magic 9 and Icewind Dale (GOG versions), which have graphics issues in Windows 10 with new-ish GPU.

The 900's (Maxwell) are XP minimum, the 1000's (Pascal) are W7 (32/64 bit) minimum and the 1600 / 2000 (Turing) are W7 (64bit only) minimum. There's a patch for that too:-
[url=https://www.pcgamingwiki.com/wiki/Star_Wars:_Jedi_Knight_-_Mysteries_of_the_Sith]https://www.pcgamingwiki.com/wiki/Star_Wars:_Jedi_Knight_-_Mysteries_of_the_Sith[/url]

(Sorry, GOG's buggy forum software borked the formatting again, just copy from the first h t t p s to the first "Sith" above and paste into a web browser.

Graphic Compatibility Mod - https://github.com/jdmclark/jkgfxmod/
32-bit installer - http://www.jkhub.net/project/show.php?projid=547 - 16-bit games can often run under DOSBox under W7-10 much better than natively under older 32-bit OS's. The reason is that DOSBox comes pre-setup for mouse, CD-ROM, Adlib / Soundblaster, Extended / Expanded memory, etc, and includes a mechanism to control CPU cycles (for games designed for sub 100MHz CPU's that would run too fast). So even though 32-bit OS's natively support 16-bit games (whilst 64-bit OS's only support 64/32 bit and need an emulator such as DOSBox for 16-bit), it's not always ideal to run things natively for reasons such as not being able to control CPU cycles.
- Many 80s/90s point & click adventures definitely run better under ScummVM than "raw" including, eg, tweaks that can skip copy protection for some.
- Likewise, if by 16-bit you meant you have 16-bit Windows 3.1 (not DOS) games, it's actually possible to run Win 3.1 under DOSBox under 64-bit Windows 7-10 and again you can control CPU clocks at the DOSBox level much better than you can running 16-bit games natively on 32-bit Windows.

Best of luck though whichever way you decide. :-)

Those machines and GPUs are too new for a retro build. Retro builds are about running old games without much fuss and those parts while fast, will just give you a headache.

Get yourself a solid Core2 or K8 box with a WinXP and a GPU which was designed with intention of running a lot DX9 SM3 games. Geforce 78xx/ 88xx/ 98xx series or Radeon X18xx/ Terascale family are safe choices. Stick to 1 or 2 cores. Be sure you can disable extra cores. Try to run GPU drivers that aren't more than a couple years newer than the games you want to play. 2GB of RAM is plenty.

Hardware like that will give you a solid DX9 XP gaming box if Win 10 isn't doing it for you. As far as I know, DX10+ games should do fine on modern hardware.

Dual boot is a headache. I wouldn't bother unless you only want to have 1 machine.

In timed missions that's really annoying. Common annoyances in C&C, RA 1 and RA2 is the scrolling goes way too fast, and the mission timer goes at least twice as fast. And UT1999 is just a chaos....

However, really early windows games with ties to f.ex. directx 3,4,5 and 6 isn't feasible on Dosbox, nor on newer os's. So, aside from Dosbox, VirtualBox / Virtual PC 2007 is another way to hamper cpu cycles/executions.

Good news. dgVoodoo2 seems to fix this. At least for the GOG version, not sure if you are trying to run the retail version?

I installed and tried Dark Forces 2 (GOG-version) in Windows 10, and yep only software rendering works. If I enable 3D acceleration in the Display options, I only get black screen and the dials which show your health/armor etc. The game seems to run though as there are sounds if I fire, but it doesn't display the 3D graphics.

However, after using dgVoodoo2 with the game, the 3D acceleration seems to work fine. So:

1. Google for "dgVoodoo2" and download it. It seems the current version is dgVoodoo v2.63.1.

2. Copy the following files from the dgVoodoo2 package into your Dark Forces 2 game installation directory:
from the directory dgVoodoo2_6\MS\x86\ copy these files:
D3D8.dll
D3D9.dll
D3DImm.dll
DDraw.dll
into C:\GOG Games\Star Wars Jedi Knight - Dark Forces 2\ (or wherever you installed the game)

Then the 3D acceleration should work right away. Remember to select some higher resolution in the options etc.

If you want to configure dgVoodoo2, read the ReadMe.html under the Doc\ directory, chapter 6. Configuring. The game seems to work without configuring though.

EDIT: There seems to be one problem though. At least for me, using dgVoodoo2 with this game seems to introduce some kind of sluggishness to the controls and graphics? It is not as fluid as without it (and without 3D acceleration). I'll still need to look into that... With e.g. Might&Magic 9, I don't recall dgVoodoo2 doing the same.

I would suggest the 32-bit Windows 7 option. It was the most backwards compatible Windows I've used. It could even run some things that Windows XP couldn't. And the 16-bit compatibility is a huge plus.

But you can run most everything these days even on Windows 10. With the combination of dgVoodoo, DxWnd and nGlide, I've not encountered a game that I couldn't run yet.