Overclocking The Radeon HD 5850
We were curious to see how much frequency headroom the Radeon HD 5850 had left in the tank, with a 2.15 billion transistor, ultra-complex 40nm GPU under the hood. So, for our next set of performance metrics, we spent some time overclocking the new Radeon HD 5850 using the Overdrive utility built into ATI's Catalyst drivers.
Ultimately, we were able to take the Radeon HD 5850 up from its default GPU core and memory clock speeds of 725MHz and 1000MHz, respectively, to 765MHz and 1150MHz, increases of 40MHz and 150MHz. While the card was in its overclocked state, we re-ran a couple of benchmarks and saw modest performance improvements of about 4% (L4D) and 6% (ET:QW).