Try these things...
1). Try running your ram @ 2-6-2-2 (or even higher until stable) and see what happens.
2). Try running your ram the 1:1 ratio if rasing the timmings doesn't work.
3). Try switching the ram to a different dimm. I have to switch mine to the second dimm for it to be stable sometimes.
Answers to your questions...
Your motherboard should be fine don't worry about it. I've been meaning to upgrade my board but my EPOX just keeps on giving. Running the ram @ 2.9 isn't that bad but I wouldn't do it. Try it @ higher timmings. Start @ 2.7 and work your way up and you raise the timmings. (ie. 2.7 (2-6-3-3), 2.8 (2-6-2-2) etc)
My questions...
I am not familiar with your board but you are running all the latest drives, etc? What type of error does it give you @ 3ghz bsod, just won't boot, freezing? LMK okay, good luck.