If you ever wanted to overclock your video card, it used to be difficult, but competition between Nvidia and ATI has forced both companies into offering proprietary overclocking software as a means of providing better value for customers. ATI’s solution is called Overdrive, and it comes bundled in the ATI Radeon software suite which is installed when you install the drivers for your ATI video card. ATI Overdrive is quite simple to use and allows you to extract maximum performance from your existing video card.
Before going any further, be warned – the fact that ATI provides the Overdrive software doesn’t mean that ATI takes any responsibility for damage which might occur when you overclock your video card. Most warranties are invalidated by overclocking, as well. Overclocking your video card doesn’t pose a significant risk of damage, but there is always a slim chance of hardware failure when overclocking computer hardware. Please be warned.
Launching ATI Overdrive to Overclock a Video Card
In order to use Overdrive you’ll need to have the ATI Catalyst Control Center software installed. In most cases you’ll already have this installed if you have an ATI video card, but it is possible to install the driver without the Catalyst Control Center. The Catalyst Control Center can be downloaded from ATI’s website.
Once installed, right click on your desktop and then click on the Catalyst Control Center option on the menu. The Catalyst Control Center will load – if this is the first time you’ve used it, it might take a few seconds. Once it is loaded, look for the Graphics menu option at the top right of the screen. Click on it to display a menu of options. The option we want, ATI Overdrive, is the last option on the list.
Understanding The Options
Before overclocking your ATI card, take a look at the options in ATI Overdrive. There are three sliders in ATI Overdrive which are important. The first two, which are grouped together, control the speed of your video card. These sliders are labeled High Performance GPU Clock Settings and High Performance Memory Clock Settings. Generally speaking, the adjustments you make to the GPU clock slider will result in a greater improvement in performance than adjustments to the memory clock, but both sliders are important.
Below, separated by a Test Custom Clocks button, is the Manual Fan Control slider. This allows you to adjust the speed of your system fan. We aren’t going to mess with this at any point doing this tutorial because the fan is already set to automatically spin faster as more heat is produced by the video card.
To the right of the sliders are three gauges. The Temperature gauge shows you the current temperature of your video card’s GPU in degrees Celsius. Right now, at idle, this will probably be in the high 30s or low 40s. Once we start changing clock speeds it could go as high as 90 degrees Celsius.
Below the Temperature gauge is the Activity gauge. This shows how close the GPU is to 100% utilization. Last, but not least, is the Fan Speed gauge. This will show you how fast the fan is spinning relative to its maximum speed.
Overclocking Your ATI Video Card
Overclocking your ATI video card with Overdrive first requires that you click on the Enable ATI Overdrive checkbox. Do that now.
The base clock speeds of your GPU and memory will depend on the ATI video card you have, but no matter what card you have you’ll want to adjust both the GPU and memory clock sliders in small increments. Adjust both sliders up by 10Mhz and then click the Test Custom Clocks button. A test pattern will appear. This test strains the GPU to make sure it can function at the new settings. If the test passes you can adjust the the sliders up by another 10Mhz. Rinse and repeat.
Eventually the test will crash or will display some strange graphics errors (known as artifacts) which are a sign that the GPU has been pushed too far. When this happens, reduce the clock speed of the GPU and the memory by 10Mhz.
Once you have reached the maximum overclock which passes the test you’ll need to verify that the overclock is stable by putting the video card through some demanding tests. A common, highly recommended free program for testing a GPU’s overclock is Furmark. Furmark puts a huge demand on the video card and will reveal any weakness. If running Furmark for ten minutes doesn’t appear to have caused any crashes your overclock is stable. If Furmark crashes, however, you’ll need to reduce the GPU and memory overclock further and try to pass Furmark again.
Overclocking The Quick Way
Using ATI Overdrive to overclock your ATI video card is easy to do, but it can take time to find your maximum overclock. Carefully adjusting GPU and memory clock settings and then testing them with Furmark can take anywhere from thirty minutes to several hours.
If you’d like a small overclock, but you don’t want to have to take the time to manually adjust the GPU and memory clock settings, you can use the Auto Tune feature. This button, found above the Temperature gauge in ATI Overdrive, runs a series of GPU load tests on your video card. It adjusts the clock speed upwards by 5Mhz each time until the load test fails or the Auto Tuner detects graphical oddities.
This won’t result in the maximum overclock for your system, but it is much quicker to perform this overclock than a manual one. You can simply begin Auto-Tune, walk away for half an hour to do something else, and come back to enjoy your video card’s improved, overclocked performance.
Getting The Most From Your Overclock
Once you overclock your video card be sure to play your favorite games to see how the overclock has improved performance. If you have a game with a built-in benchmark utility, use it to compare your system before and after your overclock.
Overclocking your ATI video card won’t make a night-and-day different, but it is possible to increase frame rates by as much as twenty percent with some video cards.