Having a strange problem.. was using P06 BIOS and updated to P09. (problem occurred in both BIOS)
When using sata mode = IDE the system will not accept a BCLK higher than about 160 (sporadically it will work at ~170).. the sytem will hang right after post, with the error code sitting at 8F or 94, seemingly random

but when setting it to RAID or AHCI mode it will boot without problem.

Using mushkin blackline 1600 set to default timings and x8 mem mult. 1.65-1.7 v
i7 920