That may depend on specifically which stepping of the CPU that you've received. The E0 stepping is pretty well-known to hit 3.4GHz with stock voltages.FYI the cpu does not overclock well at all. I tried to overclock it when it first came out with the best cpu cooler and was less than 200mhz overlock for a massive cpu temp increase. Not worth it.
Just a quick update for those who might be interested: I've got my Q9550 running at 3.6GHz at 1.2375V. When I try 3.8GHz or 4.0GHz, I cannot boot my system, unfortunately. I suspect that my RAM is my limitation as most P5K-E users seem to hit an FSB wall at about 470MHz anyway (from what I read on various boards online last night).
I've been running Prime95 since midnight Central time and it's still going great as of 8:00AM this morning. Temps on the cores range between 50 and 62 degrees F. (EDIT: I've got a Corsair H50 cooler on the CPU for those who're interested in knowing that.)
Now I'm debating on which card to shoot for.
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