The 9 months dead pc HORROR (please help)

I built a new MircoATX rig about 9 months ago. It still isn't working. As time went on, it would freeze earlier and earlier in the boot process, and now I can't even start windows or install a fresh copy.

PARTS

• PSU - OCZ 550W ATX12V / EPS12V PSU
• MOBO - MSI 880GMA-E45 AM3 AMD 880G
• VID - SAPPHIRE VAPOR-X Radeon HD 4890
• RAM - Mushkin 2 x 2GB 240-Pin DDR3 1333 (PC3 10666)
• CPU - AMD Phenom II X4 810
  
• OLD MOBO - ASUS M4A785TD-M EVO AM3 AMD 785G
• EDIMAX EW-7128G Wireless Card

THE STORY
At first, Iinstalled XP 32bit on it and had it up and running decently. I say that because initially it would randomly lock up where my mouse wouldn't move and hitting caps lock and num lock wouldn't affect the keyboard's leds. This however, was kinda rare and I seem to remember it going away for the most part.

Then Windows 7 came out.

I had all kinda of problems installing 7 (64 bit Professional); it locked up on the Setup is Starting screen a few times, but then went through all the way ate some tries. When I installed the vista 64 drivers for my wireless card (which as of yet doesn't have Win7 drivers), it locked up, I rebooted, and went into an awful cycle of startup repair, freeze at starting windows, startup repair, starting windows freeze again, over and over. It finally worked and I was able to System Restore back before I installed any drivers other than the default windows ones, but whenever I installed any drivers, be it audio wireless or ASUS's EPU engine, the same startup cycle occurred.

I decided to go back a step and try Vista 64, since I still have a copy lying around. That installed flawlessly and I was able to put my drivers on. Very quickly though, it started to hard lock again. I could play Borderlands flawlessly on the highest settings for 20 minutes, then exit to desktop, open a flash video, and crash. I could sit on the desktop for 3 hours, but once I opened up Firefox and browse for a few minutes, crash.

I went back to trying Windows 7 because I like to think that magic exists, but sadly no. I managed the install, but came up with the same exact problems as before, even with no drivers at all, which is the way I kept it.

Now I have gotten to the point where I turn the pc on and no video, integrated graphics or video card. I decided it was the fault of the motherboard, and ordered a new one.

Things I've tried, all unsuccessful:
-At one point, the psu that came with my case died in the middle of a game of STALKER, so I ordered the OCZ
-memtest86+: Passed multiple times for very long periods of time (2+ hours, overnight as well) on both sticks and then each individually, in the slot closest to the cpu.
-swapped out hdds and format, then reinstall operating system (done multiple times throughout the whole process)
-taken out wireless card and video card and run on onboard video
-ran prime95 for extended periods of time: this is where it got interesting. I can easily trounce the all around test and short FFTs test, but the long FFTs test causes a lockup after the first part of it passes on all cores. It looks like a normal lockup with my 4890 in, but when just using onboard video, a red checkered pattern appeared on the side of the window and flickered a bit (this i can no longer do though, because I can't load any operating systems )
-RMAd BOTH the cpu and the motherboard.
-Finally, just today I got the new MSI mobo, and despite POSTing (which my old one can't seem to do anymore), it still freezes when trying to start Windows or install it (at the Windows Setup is Starting... screen)

An interesting thing to note (I guess) is that whenever I use the onboard video (its happened on both of my motherboards) some pattern of red checkers or stripes gets thrown up during the freeze, as captured here

If any of this needs elaboration (or was completely incomprehensible) just let me know, and of course any ideas are welcome! ray: