ahh okay pcfreak, i have seen your post here and on the members forum from ASUS. I to have copied everything you have tried, my pc is stable at 220HTT, 800divider no problem @ 866 8-8-8-8-24 1.65v

As soon as i try 1 Mhz higher on the fsb, pc wont boot unless i drop divider to 400 which is terrible!533/667 = no boot.

Whats the solution out of this? Different mobo? Different memory? It seems its not cpu specific but more down to how the mobo deals with the memory?