ATI R600 PRO has 256 bit memory, to go up against NVIDIA 8600 GTS
 

The R600 PRO will have 256 bit memory and it will use GDDR4 at high clock speeds which should be enough to beat the Geforce 8600 GTS, even the overclocked ones.

The Radeon HD 2900 PRO will simply have more memory bandwidth, but the chip will be as big as R600 and will eat a lot of power. At the end it will bring you the performance, but it will be an expensive card for ATI to produce.

http://www.fudzilla.com/index.php?op...05&Ite mid=34