ATI seems poised next month to release its R590 chip as the Radeon X1800 GTO, with support for a whopping 256MB of graphics memory. Sources claim that the X1800 GTO boards will retail for around $279.

The R590 has also been touted in the past as a 80nm die-shrink of the R580, better known as the basis of the Radeon X1900 CrossFire Edition, X1900 XT and X1900 XTX.
The same sources also claim that ATI's next-generation R600 part will be shipping in October of this year, fabricated at 80nm.