Hey man, I have the Asus M3A32-MVP and although I don't have a Phenom CPU, I can tell you from my personal experinces this is a great board. I find that it does a real well job at overclocking my 6400+ and RAM.
You might want to check to see if your PSU is doing a good job or what settings you are useing in your BIOS. Then again, thier have been quite a few people who have complained about this board so, maybe it ain't working out for you, just tyring to help.
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