Have you tried using different RAM chips? Macs and PCs are different, sure. But one thing they share in common is ram timing. I had nothing but weirdness for weeks when I upgraded my ram. Turns out the ram stick's clock speed was using an unsupported multiplier. It'd work fine for awhile, but then it'd freeze up, crash, reboot unexpectedly...you name it. My ram sticks have to use whole number timing, like 7ns and 10ns, instead of 5.5ns or 8.5ns. Newer AMD cpus may have a much lower tolerance to these ns timings than previous editions. If you transplanted your old ram to the new mobo/cpu, then that could be the culprit. What you're describing is a memory I/O issue, and having the wrong ram can cause disk drive corruption, stuttering audio, out-of-sync video, etc. You may not have to buy new sticks. Your bios might have an option to ratchet the speed down or up...