ok mate, fine, you sort it out. I didn;t say buy a new psu, i said borrow one. Plus you said NO system specs were noted, actually the psu was, and that was what i wanted to see.
VPU, you mean GPU? And what "exactly" do you mean by frying?
The system is more than one part. If it is underpowered, you will see 12V rail droop and BSOD's, random freezes, graphical glitches etc. I very much doubt after 3 different GPU's that the GPU is the fault. I would almost bet my last dollar that a cheap, underpowered PSU is at fault. Due to the quality of the psu mentioned, he probably is getting 350W at best, which is borderline for his system under normal operating temperatures (ie efficency of 70% for a cheap PSU is measured at 25oC - not operating temps). That means if he is opearting at 40oC he is likely to get an efficiency of less than 70% which is less than 330W. ALSO I dont even know yet what the amperage is on that 12V rail, which is arguably more important. So before you dismiss the PSU and get the 4th GPU out, have a think.
KINETIC
Download Speedfan and post your 12V rail please. What i am looking for is that your 12V and other rails are within specification for ATX PSU's. If the drop you will risk damaging memory, cpu and gpu.
I believe you are having issues due to your PSU being underpowered. PS, Zeno, it has nothing to do with watts it has to do with the efficiency of the PSU. Right now, i am convinced after 3 GPU changes that his PSU is either faulty or underpowered causing the reoccuring issues.