Overclocking The Radeon HD 5870
With a 2.15 billion transistor, ultra-complex 40nm GPU at the heart of the card, we were curious to see how much frequency headroom the Radeon HD 5870 had left under its virtual hood. So, for our next set of performance metrics, we spent some time overclocking the new Radeon HD 5870 using the Overdrive utility built into ATI's Catalyst drivers.
At this point, at least as far as our early reference sample is concerned, it looks like the Radeon HD 5870 doesn't have much frequency headroom left. Of course, that could change when AMD's board partners launch products with tweaked voltages, coolers, BIOSes, etc.
With that said, we were able to take our Radeon HD 5870 up to a stable 890MHz for its GPU and 1290MHz (1.29GHz) for its GDDR5 memory, up from its stock 850MHz and 1200MHz, respectively. With the card overclocked, we re-ran a couple of benchmarks at a resolution of 1920x1200 with 4x anti-aliasing and 16x aniso enabled and saw some modest performance gains.
We'll revisit the topic of Radeon HD 5870 overclocking when we get in some cards from third-party AIB manufacturers to see if the story changes at some point in the future.