I heard that it has something to do with the L3 cache, but that's all I know. Yup, here it is, from Wikipedia:
"Before Phenom's release, it was discovered that a bug in the L3 cache in AMD's quad-core processors can cause a system lockup in rare circumstances. Phenom is affected by this bug up to and including stepping B2. There exist software workarounds to prevent this problem from occurring, although the workarounds typically employed incur a considerable performance penalty. This penalty was not accounted for in early pre-release previews of Phenom, so the performance of early Phenoms delivered to customers is expected to be somewhat below the benchmarks in these previews. Updated CPUs with the bug fixed will be named Phenom 9550 and 9650, and are supposed to arrive "mid to late Q1 2008." "
Phenom II X4 925c2 @ 2.80GHz (95W)
OCZ Platinum PC3-1333 2x2GB 7-7-7-21
Raidmax RX-500AFCheck it out.