Bit Tech published pictures of the upcoming Super Overclocked Radeon HD 5870 graphics card. This custom-design model features a GPU clockspeed of 950MHz and 1GB GDDR5 memory clocked at 5000MHz. The card uses Gigabyte's 2oz copper PCB technology and features better caps to enable more stable overclockers. The cooling solution uses four heatpipes and two fans, but doesn't exhaust the hot air out of your case. This new model will be sold in the UK for £434, quite a lot considering that a standard Radeon HD 5870 is sold for under £320.
In addition there's GPU and memory voltage changing options in Gigabyte's tweaking software and as with high-end motherboards, voltage read points on the board for overclockers, although they aren't particularly well designed - they're just small solder points.
The HD 5870 GPUs themselves are clocked at 950MHz - up from 850MHz retail stock, and they're cherry-picked dies, using a method Gigabyte calls the "Gauntlet" régime. This process was first started with the GTX 260 and 275 last year, but unfortunately for Gigabyte, Nvidia promptly discontinued the supply of those chips, so it was unable to really see the idea into the market.