Overclocking your graphic card is the easiest way to increase your system’s gaming performance. Though a good CPU is important for gaming, GPU, aka graphic card determines how good your gaming experience is going to be. A system’s gaming performance is determined by its graphic subsystem and overclocking it can make a lot of difference. For eg: if you get 35 FPS in a game, chances are there that it gets choppy during intense combats where the GPU has to render more number complex objects. Overclocking your GPU will increase the number of frames rendered by it per second and that can have a positive impact on your gaming experience.

To overclock a graphic card, you need the following

• A graphic card
• MSI Afterburner
• GPU-Z
• 3D Mark 06 (optional)
• A good power supply
• Good cooling inside your PC case

Note that you need a good power supply (PSU or SMPS) for overclocking. This is because the PSU is the component that provides/distributes power to all components of a system. Since overclocking increases power consumption the PSU should be able to handle the increased load. If it can’t provide enough power, it may shut off or even explode taking out other components along with it. A good power supply not only provides its rated power, but also “clean” power, with the least amount of ripple. If you have a good power supply, you can safely overclock your PC components.

How to overclock a GPU?

Install MSI Afterburner. This tool is based on the venerable Rivatuner.  But I prefer Afterburner just for its intuitiveness. It’s extremely easy to use that even a first timer will be able to use it right away. Below is the screenshot of Afterburner. The main window has 5 sliders – Core Voltage, Core Clock, Shader Clock, Memory Clock, and Fan Speed. If you are using an AMD/ATI card, you will see that the slider Shader Clock is not available for adjustment.

Before overclocking, you need to increase the fan speed. Just move the slider under Fan Speed to the right and make it 80% and press Apply. If the slider is grayed out, select the button Auto.

To overclock your GPU, follow the steps below.

1. Increase Core Clock

Overclocking the Core yields the most performance boost in most of the cases and for this reason, you should always try to overclock the Core Clock to the maximum your card allows. The second slider is Core Clock. Use it to increase the core clock by 10MHz and select Apply. Open GPU-Z and keep it side-by-side to see if your overclock takes effect (Don’t consider the values shown by Afterburner’s hardware monitor as it shows only the 2D clocks now).

Now you have to stress test the GPU for stability. Select the icon K on Afterburner. This will load MSI Kombustor. By default, it won’t show the GPU temperature. Press T on keyboard to toggle temperature graph and closely monitor the temperature. Before overclocking, you have to know the max safe temperature of your graphic card. You can do that by checking your GPU’s specifications. You should also ensure proper cooling. Run the test for 10 minutes. If your graphic card isn’t stable, you may get BSOD, system lockup or graphic artifacts. If your system runs fine, you may proceed increasing the Core by 10MHz.

Do the same procedure (increase 10 MHz at a time and stress test) until your system gets unstable, that is, your system crashes, becomes unresponsive or produce graphic artifacts when you run Kombustor. Once you have found the max overclock, reduce 10MHz and run the stress test for two hours. If your system doesn’t get locked up, you are lucky. If not, reduce in 10MHz increments and do the stress test until the GPU passes the test for two hours without crashing.

2. Increase Shader Clock

Now that you have found the max Core overclock. Now select Reset in Afterburner to reset all settings. Increase Shader Clock slider by 10MHz. run the stress test. Find the maximum Shader Clock just how you just did with Core Clock.

Note that I’m using a Radeon HD5770 which doesn’t have the shader clock and hence the slider is not activated in Afterburner.

3. Increase Memory Clock

Just like Core and Shader clocks, you can also overclock the memory. Reset everything to stock settings by clicking Reset. On Afterburner, increase Memory Clock by 10MHz. Do the same thing you did before to find the maximum overclock.

4. Core and Shader

Now that you have found the maximum core and shader overclocks. Now you have to set the maximum overclock to both core and shader and see if your graphic card successfully passes the stress test. On Afterburner, increase both core and shader clocks to the max values you have just found and select Apply.

Now run Kombustor by clicking K on Afterburner. Run the test for two hours. If the card isn’t stable, reduce shader clock by until you get stability. You may also reduce the core clock a bit for stability.

5. Core, Shader and Memory

Now, set all clocks to the maximum you just found and run the stress test. If the card isn’t stable reduce memory clock until you get stability.

Voltage Tweaking

Note: If you don’t know what you are doing, it can permanently damage the graphic card. If you don’t know the max safe voltage for your GPU, Google it. You may be able to find that in overclock.net and extrmesystems.org

MSI Afterburner makes it easy to increase the core voltage on supported GPUs to push your graphic card even further.  By default voltage tweaking is disabled. To unlock, select Settings and in the next window, select Unlock voltage control and Unlock voltage monitoring.

Now you will have the Core Voltage slider unlocked. If you want to overclock the core and shader even further, you can increase the GPU V-Core in 10 mV increments and overclock these two clocks just like you did before.

A Great Tip

This may sound trivial but if you are in a hotter place, just switch on the AC and bring down the atmospheric temperature to 22 C or below.  This will certainly increase your overclock.

My MSI 5770 HAWK is able to reach 1GHz with 1.3v.

Aah, and one more thing, My graphic card reaches 1GHz only if I increase the GPU V-Core to 1.3v. But when air conditioned, it reaches the same clock speed with no bump in V-Core