To take a quick look at overclocking we fired up AMD Catalyst Control Center and used AMD Overdrive to overclock the Sapphire Radeon HD 7970 Vapor-X 3GB video card.
The Sapphire Radeon HD 7970 Vapor-X comes clocked at 1050MHz on the core and 1500MHz on the memory. By using OverDrive in CATALYST Control Center (CCC) you can raise or lower the clock frequencies within the parameters set by AMD. For this card AMD set limits for this particular BIOS to 1500MHz on the core and 2000MHz on the memory.
We used CCC and found that with the power control settings maxed out at 20 we could hit 1235MHz on the core and 1700MHz (6800MHz effective) on the memory. The core clock speed can likely go higher and can if you install a 3rd party overclocking utility that allows voltage increases. We are very happy with this overclock as we are 185MHz over the already overclocked cards base core clock speed and 200MHz higher on the 3GB of GDDR5 memory.
Let’s take a look at some Futuremark 3DMark11 on the performance preset to see how the overclock helped performance.
Sapphire HD 7970 Vapor-X 3GB at 1050MHz core and 1500MHz memory:
Sapphire HD 7970 Vapor-X 3GB at 1235MHz core and 1700MHz memory:
We tried out this overclock with Futuremark 3DMark 11 on the performance preset and saw the score go from P9209 to P10394, which is a 12.8% improvements from the cards factory settings. Not a bad overclock and a significant performance increase for free!
It should be noted that when we overclocked the Sapphire HD 7970 Vapor-X 3GB that we left the fan on auto and it was running at 1.2 GHz on the core just fine! After running two passed of 3DMark11 we noticed the core temperature hit 63C. Not bad for such an overclock!