download prime95v25.4, orthos, everest, coretemp, cpu-z as a base. my pref is for prime95, run 8-12 hours small fft's to test cpu stability, blend - same hours - to test system stability. Other people disagree, and it really does depend on whether your gaming/browsing versus rendering, or other stressful-software apps.
Your e6600 (iirc) should get 3.0-3.2GHz easily enough. You may find yourself tweaking volts (vdim for memory to 2.1 likely, vcore for cpu to god-knows-what-gets-ya-stable), a lot will depend on your cooling.
Ideally, go up fsb in small steps (~10 Mhz), then run a quick, orthos or prime, small-fft to see if it can live for 10 or 20 minutes. At serious intervals, one's you'd be happy with, e.g. 2.8-3.0-3.2GHz, kick it for an overnight run. leave something running to measure temps, like everest, so you can see that you're still below, for example, 70c per core (absolute) max.
That's a very rough guide. see how you get on and post back your results, mate, and best of luck.

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btw, you'll also need memtest86+. this also takes several hours to run, so best again to do these overnight. if you do it within windows, open enough sessions to cover all your physical memory.
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