Hey there!
I have been having a very strange problem with my pc lately. All was fine until a few weeks ago, when suddenly, older games (e.g. Hitman Absolution) had severe fps drop spikes and more modern and demanding games (e.g. MGSV) caused my pc to freeze after about ~1-2 minutes of playtime, sometimes so badly, i had to disconnect my pc from the current. I don't know if it's important, but my screen doesn't just go black or white, sometimes it goes blue, red, green, etc. Now, i thought that this might be a software-related problem, and so i did a complete reinstall of my OS, but that didn't work. After that, i moved my game directories to a external ssd, went to tech support who checked the hardware and ran several stress tests, all of which were perfectly fine, but up until now, nothing has worked to resolve this issue. Here are my specs:
Intel i7-6700 3.40 GHz
32 gb RAM
Windows 10 64-bit
nVidia GeForce GTX 980 Ti
i'd appreciate any kind of help, i've never seen anything like this before and i have no idea what to do now.