I have a P5K-Premium made in China rev 2.00g and had a flaky boot problem....it was because the vid card wasn't seated properly, i'd bumped it when doing stuff in the case!

Aside from that one session where it caused me grief it's been running fine with 8gb of ram and my Q6600 @ 3.6GHz with 1.4v real and 4 x WD Raptors in raid 0. Overclocks set and stick fine in bios, no problems at all, great board so far after a few months use.