Sapphire appears to have leaked details on ATI's upcoming Radeon X1900 series graphics cards. According to card specs available on the company's web site, the Radeon X1900 XTX will have 48 pixel pipelines and be clocked at 650MHz core and 1.5GHz memory.
A Radeon X1900 XT will have the same number of pixel pipes, but slightly lower 625MHz core and 1.45GHz memory clocks. Interestingly, the Radeon X1900 CrossFire Edition will be clocked at XT rather than XTX speeds.
TechReport
TechReport