Noted Finnish overclockers Sampsa Kurri and Ville Suvanto achieved graphics engine clocks of 1.003 GHz and a memory speed of 1.881 GHz (940.50 MHz DDR (dual data-rate) memory clocks) with maximum system stability and no visual artifacts.
The team, optimistic that higher speeds could ultimately be achieved with the Radeon X1800 XT, attained the record speeds using a custom-built liquid nitrogen cooling system that cooled the graphics processor to minus-80 degrees Celsius. "We're just warming up," joked Kurri. "But we believe that the Radeon X1800 XT has even more over-clocking headroom, and in the coming weeks we expect to achieve higher clock speeds and even greater performance levels."
A screenshot of the overclock can be found here.