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Overclocking & Tweaking
Before 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 will give you the best possible results by far.
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 an 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 runs 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 start to show artifacts such as white dots ("snow"), you should back 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.
| Reference Clocks |
Default on this card | Maximum overclock | |
| Core Clock Speed 3D |
Even in Crossfire mode the cards can be overclocked, we however did not have a lot of margin as being CPU bound is getting a big problem with so much raw horsepower under the hood. None the less we could set the core at 667 MHz and the memory at 750 MHz easily. The differences in overclocking however is NIL and you should probably wonder if it is worth the hassle at all.
Results will vary per card, and you might need to back down a little the minute you see artifacts or simply want to play it safe. None the less, tweaking is a simple trick to get some more bang for your buck. For overclocking performance differences, look at the chart below:
Overclocking your card too far or constantly to its maximum limit might damage your card and it's usually not covered by your warranty.
You can alter the default clock settings by using Rivatuner, which you can download here.
One small sidenote: Our overclocking results are never a guarantee for your home grown results. Manufacturers' choices in components differ often per batch and so will the end-result. This however is a good indication of what is (or isn't) possible.
