@MichaelM
I was having the same issue, but I updated to the bios mentioned in this thread, and its all working now
I tried overclocking by using the turbo but it didn't work at all. Just stuck at 3.4GHz on all cores with IBT
I resorted back to my multiplier+C2 but it would only initially go to 4.6GHz, a few days later it let me go back to 4.7GHz...haha so I think i'll stick with this way for a while before I attempt to try turbo overclocking again.
Will these settings apply to the MSI Big bang Marshall?
Just had mine delivered along with a 2600k and will be having a mess about with it tonight.