Hello,
Try a more thorough test using Memtest86+ (get the floppy version):
http://www.memtest.org/#downiso
Should go through every single bit in your RAM to find any problems.
If the RAM passes that test, then try utilities on the boot CD image here:
http://www.ultimatebootcd.com/
Has some motherboard diagnostic tools you can use to check devices and such (also contains memtest86+ and other memory tests, but you have to burn this to CD).
Hopefully, your RAM is fried instead of the mobo...
Good luck