My computer nightmare

Hardware Hub CPU
1

My name is John and I'm new to forums. I've always watched the Tek on youtube but I really need some help. Sorry for the long paragraph but I assumed it would be best to give as much information as possible.

I have a fairly old computer due to do my current financial status. Ao this december I decided to overclock and unlock cores on my AMD 555 BE to beef it up a little. I unlocked both cores, and overclocked it a little no problem. Unfortunately it wasn't stable enough with unlocked cores so I set everything back to default. The next week my computer deteriorated to it's death. In the beginning it would bluescreen. As time progressed, the computer would instantly lose display and the power botton was unresponsive. This happened continously  and more frequently till it eventually would not post. All fans would power on max and power button was unresponsive. I RMAed my motherboard and recieved a new one, same problem. I tested both a diffirent PSU and graphics card, same problem. I tried exchanging RAM and using diffirent slots, same problem. So I narrowed it down to the only possible conclusion; the CPU must have "died" from the overclocking and core unlocking. I recently ordered an AMD 1055t after checking if it was compatible with my motherboard. VOILA! Booted right up to windows...LOST DISPLAY AFTER 15 MINUTES! Now it's the exact same issue, max fans, no display, unresponsive. What is going on?... I just don't understand.

2

Well, who is the motherboard manufacturer? When I RMA'd my MSI GTX 560-Ti Twin Frozr II for severe artifacting and driver crashes (even after clean driver install), they sent me back the EXACT unit I sent in (not an identical, new GPU, but the very unit I sent in; same serial num). I called and complained, and they sent me a GTX 570, which shortly started artifacting again (though no driver crashes), which forced me to back to my old Radeon 5830, zero problems, actually ran Skyrim smoother than 570 (probably due to bad memory).

Now MSI GPU's are on my blacklist, and they have one of the worst customer services I've ever had to deal with as they are impossible to reach by phone, and it takes 30 minutes to fill out a contact form because (at least back then) had a whole bunch of unnecessary, non-applicable, but required fields to fill out.

3

The motherboard is an MSI 770-G45 and the GPU is an XFX 5770. MSI did accept my RMA and I got my motherboard back after about a month. I forgot to add that the reason I sent my motherboard back was because while I was trying to fix this issue my motherboard actually caught on fire.. Could this be a powersupply issue? Perhaps the power suppy has some really messed up voltages and is killing the motherboard and CPU?.. And I tried removing the SATA connectors and powered on with only essential hardware, no luck... Thank-you though.

4

Could be either, or both.