To simplify for the reader, an oversimplified version of my question comes first (though perhaps it is enough).
Is it possible for a power supply to be failing in such a way that it causes problems which would normally appear to be GPU related symptoms? (even though said PSU is rated for said GPU)
Fully explained problem
So, I have a kinda old (maybe closing on 5 years) windows XP system. I've been trying to repair it for awhile now cause I just didn't have the money to replace it. It's kind of been a long process, and the symptoms have evolved over time.
I first noticed problems when playing Path Of Exile, the system would freeze up (no BSOD, just frozen). No matter what I did to lower the requirements, it would just happen every once and awhile, but limited to the game. After awhile these freezes would actually dump me back into the desktop, but at the lowest resolution possible and the colors would be all distorted.
Obviously, I assumed "bad GPU" -> replace.
to shorten the rest of the story (sorry):
-The GPU has been replaced with a new Radeon R6570 1GB (not the best, but scrapping this system as soon as I can afford to)
A similar but different problem occurred (to be described shortly) which resulted in
-complete HDD reformat and windows XP reinstall (SP3) -replacing the motherboard and CPU with a used but functional pair (friend hand me down) -similarly replaced RAM
So now, there are pretty much NO remaining elements of my ORIGINAL system, except for the wireless PCI card and PSU. (Note the HDD is only 2 months old, so I don't think its corrupt). Nonetheless, a very similar problem persisted throughout each stage, even though it has been in a slightly different form since the GPU was replaced (which was replaced TWICE, by exchanging what I thought was a "faulty" first one into the store).
The problem exists outside of games, or really taxing operations. What it can best be described as is a checkerboard pattern of small, colored, somewhat transparent pixelated regions on my screen, usually blue or yellow (but always the same color at once). Occassionally, but not always, everything freezes up like this for 5-10 seconds, then the monitor goes black and comes back after a moment all systems normal (though occasionally the browser window viewport will remain forever black until restart).
Normally, this screams GPU to me... but having replaced it twice, uninstalled/reinstalled/updated the drivers 4 times, reinstalled the entire OS, even replacing the damn motherboard.... I don't see how it could be. Since the PSU is the ONLY thing I have yet to replace, before I dropped another 50$ on one I wanted to ask the brilliant minds here... could it ACTUALLY be the problem?
note my current PSU IS rated high enough to handle this GPU (450W), and no... nothing is overheating.
Thanks so very much for your help. I'm sorry this was so long. I'm just SO frustrated >_<