ram settings

I have tried all the settings that I can find but without success, all I
seem to be able to do is set the RAM to Unlinked.
On my old gigabyte mobo I could set the ratio from 1:1 to 1:2 and various in
between but on my Striker Extreme I cannot find this setting. My B3 Q6600
maxes out stably at 2.8 and slightly unstable at 2.9GHz. All my attempts at
3.0GHz have failed at the POST stage. I even tried 1.4V core but without
luck. The Striker seems to be a dud, I could have saved a load of money and
bought a p35 mobo.

Robin