I'd just like to say that I have the exact same problem as incubus. I returned my Gigabyte MA770T-UD3P a few weeks ago because it had some network difficulties, and finally got my substitute today, a Gigabyte GA-990FXA-UD3. On my last board, my Phenom II X2 550 could easily be unlocked to a quad-core and overclocked to 3.7 GHz and still be completely stable in Prime95 for 12 hours. Now, those settings cause it to crash the very instant I try to do pretty much anything, and it doesn't fare much better as a triple-core. This is seriously annoying. I didn't return my old board to get drastically reduced performance. Is there any way I can make my CPU work on my new board as an overclocked quad-core?