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Overclocking & TweakingBefore we dive into an wide-ranging series of tests and benchmarks, we need to explain overclocking. With most videocards, we can do some easy tricks to boost the overall performance a little. You can do this at two levels, namely tweaking by enabling registry or BIOS hacks, or even tamper with Image Quality. And then there is overclocking, which by far will give you the best possible results.

What do we need?
One of the best tool for overclocking NVIDIA and ATI videocards is our own Rivatuner that you can download here. If you own a NVIDIA graphics card then NVIDIA actually has very nice built in options for you that can be found in the display driver properties.

Where should we go ?
Overclocking: by increasing the frequency of the videocard's memory and GPU, we can make the videocard increase its calculation clock cycles per second. It sounds hard but it really can be done in less then a few minutes. I always tend to recommend to novice users and beginners not to increase the frequency any higher then 5-10% of the core and memory clock. Example: If your card would run at 300 MHz then I suggest you don't increase the frequency any higher than 330 MHz.

More advanced users push the frequency often way higher. Usually when your 3D graphics will start to show artifacts such as white dots ("snow"), you should go down 10-15 MHz and leave it at that.

The core can be somewhat different. Usually when you are overclocking too hard, it'll start to show artifacts, empty polygons or it will even freeze. I recommend that you back down at least 15 MHz from the moment you notice an artifact. Look carefully and observe well.

All in all... do it at your own risk.

The Radeon x800 XL seems to be a very nice card to overclock.

You will benefit from overclocking the most with a product that is limited or you may call it "tuned down". The XL is exactly that as it can benefit from a higher core speed and memory bandwidth really well. We know that the graphics core is often limited by tact frequency or bandwidth limitation, therefore by increasing the memory and core frequency we should be able to witness some higher performance results. A simple trick to get some more bang for your buck. In the charts above you can see Doom 3, Aquamark 3 and Half-Life 2 at work with the default clock speed and in overclocked status which was 446 MHz on the core and 544(x2) for the memory. Obviously the overclock matters.

Overclocking your card too far or constantly to its maximum limit might damage your card and it's usually not covered by your warranty.

Once again, the results are with 6xAA and 16x AF enabled. The default clock setting you can alter them by using Rivatuner, which you can download here. We pushed everything to 446/544 where things remained 100% stable.

One small reminder though, our overclocking results are never a guarantee for your results. Manufacturers' choices in components differ and so will the end-results. This however is a good indication of what is possible (or not).