Yes, that's the thing. It needs insane voltage levels vs 21x. Asus really needs to fix it reverting to 20x under load... :(
it seems that also the p6t ws revolution has this feature: look at the new bios
P6T6 WS Revolution BIOS 0407 - 2009/03/16 update
2. Support i920 CPU ratio up to 21 and i940 up to 23 in BIOS setup.
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zolkorn that option u showed is just a tdp limit option .. not a turbo mode enabled..
the turbo mode is in the cpu configuration