I have a question about video card overclocking: are pre-overclocked videocards (like my XFX 8600 GT) overclockable like an normal 8600 GT in a pre-assembled computer? I was just wondering since my card was already overclocked. And if they are, are they any harder to overclock? Thanks for taking the time to read.

Probably, but i wont go too far. You also need to be very wary of its temperature as pre built pc's usually have poor ventilation.

Don't worry, I built my pc myself. This is the link to its casing- http://www.silentpcreview.com/article200-page1.html

I was just wondering if I could push my card just a little bit more to squeeze out that last bit of performance. Thanks for replying so quickly.

To be honest, you may gain 1 or 2 on framerate but not a great deal more i suspect.

Okay, thanks:). I guess that's not worth the risk.

I personally would say so, others may disagree as im not a major overclocker. My system is 7% oc'd and my gfx is 12% oc'd.

It's okay to overclock, but remember; it's shortens the lifespan of any hardware, especially a gpu.

It's not really worth it to overclock an 8600-series card. Video card overclocks are really only worth it on high end cards, and the 8600 series is nothing if not mid-range. You really wouldn't notice a performance increase, so might as well not void the warrantee.