The something else is a little bit broad. :D The memory is the best guess from your list. I'll try with 1.65v rams only. Maybe that helps. Thanks!
edit:
I got a "display driver stopped responding and has recovered" message just now. :D I don't understand. I used the same driver with the new mobo too, and with that it worked perfectly. At least I played and browsed about 10 hours with it without a single error message, crash, etc... I'll test that system further maybe it needs time to produce the same error messages. If so, then the problem is with the video card or the driver. Btw. is it sure that this is an issue with the ram on the mobo? I mean the video card has a ram too...