I've been going through the same pain with the plus board, but here are some quirks that I've found;
Bios at 6x, fsb 1333 - Boots at 2.00Ghz, CPUz reports 3000Mhz, Sandra reports 3000Mhz, Sandra Bench 18718/14463 (by comparison, the e6600 is 21685/15090) Coretemp is 38/38c
Bios at 6x, fsb...