Recently there have been a few “overclocked out of the box” video cards offered, including the newer revisions of the Radeon X1800 XT. Some ATI providers (ASUSTeK, HIS and Sapphire) have been shipping cards set at 700MHz GPU, 75MHz beyond stock, and higher memory frequency as well, to further boost performance. The older versions
of the board, however, which are most common and most readily available, aren't able to handle this overclock because they are not designed to support the extra needed voltage. Ultimately, people trying to flash older revision boards with a BIOS set to overclock may result in a card that dies prematurely. In response, these manufacturers are revamping their PCBs to bring better voltage regulation. There isn't a price difference between new or older PCBs, but overclocking is sure to have much more success with the newer.