Easiest things to do first, in order:
1) Run CrystalDiskInfo, make sure SMART attribs on the disk are not flagged (30 secs)
2) Run Prime95/IntelBurnTest (works on AMD fine) and watch temps with RealTemp/CoreTemp/HWiNFO (5 mins)
3) Run MemTest86 in the method I described in my other comment (20-60mins)
If it passes all of those (and your temps are well below TJMAX, not sure what that is for your AMD but usually around 100C) then it's some other hardware failure. Next suspect would the the GPU itself.
PSU failure is always a possibility but when they die, they usually completely die. Like, don't work at all. You can't test the PSU without a physical PSU tester (Amazon, ~$10) or you could test it by swapping to a known good PSU.