@HellzKillerRox Any game that runs in Windows 11 would also run in 10. You'd be erasing the C drive, so any games installed there would need to be reinstalled, and you'd need to use the standard "locate game" option for games installed elsewhere, or else tell the launcher to reinstall them to the same location so as to recreate the required registry entries. So it would be some work, but not a permanent barrier to playing those games.
I can't tell you that running Windows 11 on unsupported hardware is in fact your issue. And I can't tell you why it would only be a problem now, although 11 is changing here and there with new updates, and it's entirely possible something recent broke the previous reasonably-good compatibility with your system. If you'd rather try a clean boot first, that's totally understandable.
Another way to hedge your bets, so to speak, would be to partition one of your drives and install Windows 10 there. You'd then have a dual-boot system and be able to select which OS to use, and while you'd need to "reinstall" Sims 3 (to recreate the registry entries), you could skip that step with any game running fine in 11. If it worked, you'd have a decision to make; if not, you'd have established that the OS is not in fact the problem here.
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