Help overclocking video card nVidia 8600

[Waffle]

I want to overclock my video card... to be able to play more than decently. I have some problems with call of duty 4 (do not say you want to play with Resolution 1680 * 1050 with all the details at the most, but almost). I have a nvidia GeForce 8600 gt of sparkle, cooled by a thermalight V2 on which I mounted a fan 7 * 7... for the rest I have a intel core 2 duo E6750 cooled with thermaltake TMG A2, 2 gb ram 677 of teamgroup. The system mounts a fan 8 * 8 located in front of the hard disk and a 12 * 12 in mining. In terms of cooling, if there should be no problems then I can proceed to a Overclock or not? This would give me significant improvement?

Expect your answers...

[SUpER CoP]

You could try RivaTuner, which has come to version 2.07, increasing gradually the clock of the GPU and RAM:
http://downloads.guru3d.com/download.php?det=163

Always Keep an eye on the temperatures and make sure artifacts are not out for example using the 3DMark applications.

[Waffle]

Ok, try with riva tuner yesterday with nvidia nTune to have increased frequency:
540 to 680Mhz core and
300 to 435Mhz for the memories
(last test values accepted by the application).
The temperature has risen by 6-7 degrees (temperature measured with the gpu gpuz) and is around 46 degrees idle.
So we say that the system in general is not stable, crashed a couple volts during the game in windows.
And the worst is that I have noticed improvements during the game, then I wonder do you need to overclock if I do not have any result, if not crash the system. I feel like with RivaTuner and see what happens. Meanwhile thanks.