Well the higher the multi the better, but i reckon its not worth the upgrade unless you are moving to quad core.
Did you really get a huge difference in FEAR with an overclocked CPU? I know CSS gets a huge increase with an OC'd CPU (from experience), although i never got much of an increase in FEAR.
What kind of increases are you getting in CSS and FEAR with and without OC? See, with my old computer (had a P4 3Ghz and a geforce MX440), i always got a huge difference in CS:S when i upped the CPU from 3 to 4Ghz. Now by your logic that means that the MX440 was being bottlenecked by a 3Ghz P4 (which is really unlikely
Hope that clears it up a bit
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