My Q9550 is currently running at 3.4 ghz with all stock voltages. But I am want a boost in FPS for gaming. Would it be worth it to overclock my q9550 to 4.0 ghz? And what would you say is the maximum vcore you could set for day to day gaming?
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On Intel's site the absolute safe voltage is 1.3625V, which is what would be safe for day to day usage. Also, the max temp is 71.4°C, I suggest you don't go above 65°C, full load Prime 95 if possible.
I wouldn't bother OCing the CPU for a boost in gaming. You already have a quad at 3.4GHz, anything more isn't going to give you much of a boost. Try OCing the GTX260, or get something better.