I was thinking of using an old FM2+ platform to cobble together a lower power HTPC/occasional old school gaming system.

The parts i have are:
Crossblade Ranger
860K (i think there's an 880K somewhere)
7850K APU (not sure how this would work with old XP era games though.
Various kits of DDR3 (lots to choose from) with some high end 2400Mhz memory.
TV card with sat cable inputs, which i think i could connect my Sky sat cables to.

WinXP 32bit and Win7 64bit.

Would Win XP Home or Pro suit better?

I was thinking since i have some spare 500GB SSDs, that i would have one for XP Pro and one for WIn 7.
How is XP with SDDs?

My thinking behind using those parts, instead of buying older hardware, was this would do for the XP era games that just work flawlessly on XP compared to later operating systems, or are all XP games just working flawlessly on Win 7 now?

As to the hardware choices, i thought i should go with something powerful enough to cover my bluray playback without jitters.

The system i use as a daily driver (not for gaming really) typically sits at just over 100W for just watching a youtube video or movie LOL

Oh, i also have a few of those ROG Front Base Dual-Bay Gaming Panels left over that go with the Crossblade Ranger motherboard. I guess that'd be too much though. No need for something like that for what i intend to use the system for.

Any advice from those with XP systems would be great.

EDIT: How does WinXP do with very large storage drives, like 16TB?
I'm going to want to install my large storage drives in the system for the Win7 OS for HTPC use, but i was wondering how this would play when i switch to XP, would XP even see a storage drive that large?

What benefit are you expecting to get from running both XP and 7? Unless you're planning on running 32 bit XP and 64 bit 7?

Ah yes, forgot to mention, it will be WinXP 32bit and WIn7 64bit.

i was thinking the media center would be better on Win7 as I have a TV card i'd like to install. Which i also forgot to mention.

I haven't used XP in a long while but from what I recall it doesn't support either 4k aligned partitions, nor TRIM nor GPT partitions. The former can be worked around but lack of TRIM is not very SSD friendly and no GPT may limit you to 2TB partitions / drives. For Blu-Ray, Windows XP needs UDF File System support patched in (limited to 2.0 and read-only) whilst W7 has native 2.6 support (some Blu-Ray's use 2.5). To be honest, you're better off just sticking with one W7 install.

Personally, I would suggest Linux instead of Windows XP. With this setup, you get the benefits of a modern OS (GPT, TRIM, 4k-aligned partitions, continued security updates, and so on), and you still have WINE for playing older games. (In some cases, WINE may be a better choice than native Windows, particularly for older games that don't work on modern Windows.)

Yeah i remembered something about a storage size limit, but i was thinking since the drives would all be seen by both operating systems, that maybe if i was already on XP playing a game, then decided to put on a movie that i would be able to do this without having to switch to Win7.

For XP games, i was thinking a 1TB drive would be plenty enough. If Win7 does XP era games, then i guess there's no real need for XP at all.

These are new copies of XP that i kept for myself. I always kept one of each OS for myself when i sold PCs. So i guess i could put them on Ebay. I'm itching to install one of them for that hit of nostalgia though LOL I haven't used it in such a long time.

For gaming, I've yet to find any game that worked on XP but not on W7. Out of all the Windows versions owned, W7 really is the most compatible I've ever used (DX12 aside). The only thing you may need is DOSBox / ScummVM for DOS games as 64-bit Windows only supports 32 & 64 bit (but not 16-bit) whilst 32-bit Windows supports 16 & 32 bit (but not 64 bit). But that's an issue that also affected XP 64-bit. And DOSBox / ScummVM work well when setup right. XP's lack of DirectX10-11 and 64-bit gaming is a far bigger compatibility problem. Even many Indie's today are 64-bit only.

There is no real reason for still using an XP 32-bits for gaming. Very rare are the games that don't run properly on a 7 64-bits if you tweak the problematic games with the appropriate tools (compatibility wrappers, (un)official patches, etc.).
You're wasting time and disk space for nothing imho.

EDIT : I totally approve what AB2012 just said above.

I thought about trying Linux Mint, but for whatever reason, laziness probably, i just assume it'll be as bad an experience as i had with Ubuntu when i tried it for like a week or so. That was back in 2015 or something, i'm sure it's better now, but it was just weird not having access to certain tools to monitor net traffic in real time with the ability to intervene (block/allow), and also not having the ability to have a fully fledged security program was a bit of an offputting thing for me.
Maybe there were such things available, and i just didn't look harrd enough.

I did like Arch more, but again, i felt kind of naked even, not having certain tools.

I don't think i knew what i was actually looking for, or to achieve when i was trying them out LOL Hmm, well i have Win7 already installed on my X470 Crosshair 7 hero system which is what i use right now for a HTPC, but i suppose i could look into getting a 5700G and mATX mobo to see if can get a system whcih uses less power than this does.

So then i could probably just make a little gaming system with that FM2+ gear, and install the ROG Front Panel as well, and pop that on Ebay for a few quid. Probably won't sell though as it's very old stuff but not yet vintage enough to be of interest i suspect. It's all in pristine condition though as these parts were bought when i was still building PC to sell, and my loft is kinda overrun with parts LOL

I don't see a reason to run XP Pro and Win7 as dual booting systems. Might as well VirtualBox and install XP in a virtual drive, use the tools to forward commands to the local video card, and only use XP in the case Win7 won't do it for you for some reason.

Edit: With tools pretty sure you can reduce the XP install to 100-200mb.

I would recommend trying it again, especially since you'll still have Windows to fall back to if you need it.

To be honest, whenever I'm forced to use a Windows system (which isn't a situation I find in that often), I find myself missing the wide variety of command line tools that come standard on Linux, and the control that Linux gives. (If I ever get a job where I have to use a Windows computer, I'll likely be installing something like Cygwin or WSL on it, and if that's not allowed, I'd argue that my employer isn't giving me the tools I need to do my job.) Or, if you want low power, get some low end mini PC. Generally, a computer of this sort might work well as a media center, and you might even be able to play some games (particularly retro games or those with lower requirements) on them. Furthermore, the lowest end mini PCs are often fanless, and they don't take up as much room.

I have AMD motherboiards going back to the Crosshair IV Extreme, (all my motherboards are ASUS) and GPUs going back to around then as well, that i kept for myself instead of putting into systems i was building to sell. Not sure why i kept this stuff as it's probably just seen as junk by many now, but it's all pristine AMD/ASUS stuff, with various GPU vendors of course (including many Nvidia incase any thinks i'm an all out AMD fanboy LOL).
So i was thinking, i could maybe use some of the things i already have.

I've always like APUs, which is why i was thinking of going with the FM2+ and the 7850K i have, but only if it played nice with XP games, but since others have informed me, it's not even an issue as Win7 will do just fine for playing XP era games.
I would be willing to get a 5700G and mATX board. I really don't like pre-builts at all, regardless how well reviewed they were.

I have a few of those 1200W and 850W ASUS Thor PSUs, and i think i still have one 550W SeaSonic GX Focus left over somewhere that would be just right.

I can only hope your machine is airgapped. Personally, I'd rather just drop in Linux and run Wine, then trying to deal with a 20 year old OS.

Well it would be when using WinXP, since there wouldn't be any need to connect to the net with it, except download drivers perhaps, which could even just be done on the Win7 OS, then boot into XP and grab them from the shared storage.

I still right now run Win7 on my X470 system though, as a daily machine. It's fully connected to the net.
It's also secure, and i'd wager a pint of beer that it's actually more secure than Win10 or Win11 are.

Not sure io could get WinXP to the same secure standard, since i haven't used it in such a long time, i'd really need to install it and take a look. Very doubtful though, simply because of how out of date browsers are for that system as there is only so much you can do with a browser to make it more secure.

As far as I recall, I guess the main possible backwards-compatibility problems Windows 7 could have, are:

- 16bit programs wouldn't work (unless Windows 7 is the 32bit version?). Like some old Windows games installers were 16bit, even if the game itself was 32bit. So you had to find some other way to install the game manually, copying files etc., or find a user-made installer for the said game.

- Windows 7, or actually Windows Vista, introduced the "rainbow color problem" that many older Windows games had in Vista/7. There were various ways to work around that though, like killing the explorer/Aero/whatever before you launched the game.

EDIT: https://www.gog.com/forum/general_archive/fix_weird_colors_in_some_old_games_under_windows_7/page1

- At some point, certain CD-based copy protection schemes stopped working in Windows 7 (and later). However, in Windows 7 it was possible to enable the parts that were needed by the copy protection schemes. In Windows 10 it wasn't, AFAIK. Or then you try to find working no-CD cracks for those games, if it allows them to run in Windows 7 (and later).

- Then there were odd games here and there that just wouldn't work in 7, possibly due to their copy protection. I have one such game, Peter Jackson's King Kong game (the first version, not the "enhanced" version with slightly different graphics). I have one older laptop with XP where that game runs fine, My other two older PCs capable of running Windows XP are too weak to run the game.

That King Kong game was released in an inconvenient time: it required a pretty beefy PC for the time... but would not run with the newest Windows. A bit like someone would release a game now that needs a pretty powerful CPU and GPU and 16GB RAM, but would refuse to run on anything newer than Windows 7. I am not familiar with the PC parts that you are going to use, but my main concern always with these "try to run an old Windows version on a modern PC" is the driver support. Ie. can you find working XP drivers for all the hardware components? Windows versions should generally be run on the hardware of their own era, not with "future hardware" from their point of view.

Also, as already pointed out, XP is probably anything but optimal for using SSD. And also limitations to using GPT etc.