I got rid of my "G" batch, L647G, and it blew. On a P5B-Deluxe, I maxed out at 333x9, no matter voltage/multiplier. Swapped for an "A" batch (L640A), first test @ 3.3ghz (367x9), rock solid Orthos stable. I'm excited to see how far I can push this chip.
EDIT: Using BIOS 1101 for my P5B-WiFi