Performance & Overclocking

Performance & Overclocking
Before we dive into an extensive series of tests and benchmarks, we need to discuss overclocking. With most videocards, we can do some easy tricks to boost the overall performance a little. It's called overclocking the videocard. 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 start to show artifacts such as white dots ("snow"), you should go down 10 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. Overclocking your card too far or constantly to its limit might damage your card and it's usually not covered by your warranty.

You will benefit from overclocking the most with a product that is limited or you may call it "tuned down." We know that this 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.

The results on both x800 cards are promising.

The Radeon x800 Pro at default clock speeds is doing 475 MHz core and 450 MHz memory (900 effective).
overclocked it was capable of running of a 515 MHz core and 560 MHz (1120 effective) memory frequency. Now that is bang for your bucks as that is XT speed, you still are missing 4 pixel pipes though.

The Radeon x800 XT was very overclockable also, yet we could not manage to push it all the way as we were CPU limited with a 2.8 GHz processor. AMD is sending in an Athlon 64 3800+ this week so expect another update soon. At default the XT is smooth sailing at 520 MHz and 560 MHz for it's gDDR3 memory. Overclocked we where able to push the board towards 560 MHz for the core and 600 MHz on its memory. Due to the CPU limitation overclocked results are not showing what they should be. You'll see that in the following benchmarks we ran.

What worried me to the up most is the heat that the card is producing. In idle we saw temperatures of ~50 Degrees C. When heavily stressed it'll rise towards 70 Degrees easliy. There even are reports from users at 80 Degrees C. ATI verified that that temperature per se is not dangerous for the graphics card, and that's true. Yet that heat is dumped inside your case. So unless your have some seriously good cooling you need to take note of the fact that the card will create higher ambient temperatures inside your case that can have an adverse effect on other components, especially an overclocked processor (CPU).