I have been having some fun (and minor scares) today with overclocking my pc, built last year with an e7400 and gtx 260, I've been playing around with the system bios and RivaTuner all day and hit what I think to be a great sweet spot considering that I am still on stock coolers + two case fans I installed today after the questions about temp the other day in this thread.
First of all I tweaked around with RivaTuner learning about what it does and how loud my gtx fan can be at 100%, I managed to push up my card's Core and Shader clock rates from 576 to 638 / 1242 to 1375 (going by RivaTuner numbers) with the fan running at 65-75%, keeping temps below 72C. The boost helped a little bit in TF2 and raised my FFIX benchmark from the original 2685 up to 2758 :lol this is where I realise my e7400 2.8 is holding me back more then I originally realised.
So after spending HOURS reading about overclocking, voltages and ratio status I found an area in my bios which does this all automaticly under something called "overclock settings" hidden away in the voltage area

I hate changing this stuff as it always gives me butterflies but I stick it on 5% to give it a go, windows appeared fine so I gave FFIX another shot and this time it hit 2909! to me that is a nice jump from just a 5% boost. I know that I should run some CPU stress tests overnight to make sure everything is ok (I am actually running Prime95 right now at 59C) but I thought i'd give 15% a shot first, it's what I am currently on as I run the tests and the new score for FFIX this time was 3112 with quite an obvious increase in frame rate due to the test not dropping frames as often.
Tonight I will allow Prime95 to continue testing and tomorrow if all goes will try out 20% cpu overclocking but I personally don't expect to go higher then that, this machine needs to last me a good while
Overclocking is awesome, quite amazed I never tried this with my old pc years ago when it started to feel slow.
*edit* 15% going by my poor math is 2.8 up to 3.2ish