Overclock your Graphics Card 

Overclocking a graphics card gives it that extra bit of performance. Advanced graphics cards sometimes ship with utilities to overclock them, such as the Vtuner utility that is shipped with Radeon 9800 XT cards. But, vendors sometimes block these utilities so that you don’t go back to them with a burnt-out card because of over heating. So, if your utility is blocked and you’d still like to overclock your card, you can use the tips we’ve given in this article. But, remember that if not done properly, overclocking could destroy your graphics card or even your PC.

nVidia cards



In the case of nVidia cards, you will use the ‘Coolbits registry hack’. If you’re adventurous (which you must be if you’re venturing to overclock your graphics card), you need to modify the registry as explained below.

l Go to Start>Run and type regedit to open the registry editor

l Next go to the keyname



HKEY_LOCAL_MACHINE\S OFTWARE\NVIDIA Ccorporation\ Global, and click on NVTweak

l Right click on the pane on the right side, click on New and select ‘DWORD value’. A new value will be created and displayed in the right pane

l Rename this value as coolbits and set its default value to 3 by right clicking on the Entry and then clicking on Modify

l Close the registry and restart Windows

A new item called clock frequencies will appear on the left pane on this window, click on it and start overclocking

If you don’t want to modify the registry yourself, you can use Coolbits software provided on this month’s PCQEssential CD. Once you unzip and run the Coolbits file, it automatically creates the Coolbits entry in the registry. Now restart Windows.

After restarting, open the Display Properties dialogue box (right click on the desktop and select Properties). Then click on Settings>Advanced>Geforce. Here, you will find a new item on the left pane called Clock Frequencies. The clock frequencies displayed initially would be the default clock frequencies. Check the Allow Clock Frequency adjustments box to start overclocking. You can increase both the memory and the core clock frequency, but be careful. You don’t want to blow up your card by overclocking it too much! Increase the clock frequency bit by bit and be sure to test that frequency by clicking on the ‘Test Setting’ tab before applying the settings.

Click on the graphics card icon in the bar menu, which appears when you click on the customize button

ATI cards



This ‘coolbits registry hack’ is not valid for cards which are based on an ATI chipset. For overclocking an ATI card we use another utility called Rivatuner, which too you will find on our this month’s PCQEssential CD (also downloadable from www.guru3d.com). Rivatuner comes with an easy to use interface. All you have to do is unzip the application, install it in the Main tab itself and click on the Customize button. On the new Menu bar that will open, click on the Graphics Card icon. Now you’ll see a new window displaying the default clock settings of your graphics card. Check the ‘Enable low-level hardware overclocking’ box and kick off with overclocking your card to squeeze that extra bit of performance out of it.Overclocking can be quite taxing , as it leads to overheating of the card. So, be sure to place an extra fan in front of your card or even use a water

cooling kit.

One might wonder if overclocking a graphics card is worth all the effort. One thing is sure that the moment you overclock your graphics card, the warranty becomes invalid. The cards that we overclocked at CyberMedia Labs were ATI Radeon9800XT and Nvidia GeforceFX5700.

The core and memory clock frequencies displayed initially on the window are your default clock settings

The Radeon reached its peak performance when we overclocked its core clock by 7 percent and the memory clock by a mere 4 percent. With these settings, performance went up by just 3 percent in 3D Mark 2001, when we tried to increase the clock speed further the performance started deteriorating, which was clear from the faltering images when we ran the 3D Mark 2001 benchmark test. The GeforceFX5700 showed a much better capacity to be overclocked as it reached its peak performance when we overclocked its core by 15 percent and memory clock by 6 percent. But again, the performance went up by just 2 percent in our benchmarks.

In short, do not expect to convert a Geforce2 to an FX5700 by overclocking it. Overclocking can give you that extra bit of performance, but more than that, it gives you the kick and the bragging rights of having been there and done that.

Ankit Kawatra