We came to know that Radeon X1900 XTX (R580) will officially be clocked at 650MHz core and 1550Mhz for the memory while the X1900 XT will be officially clocked at 625MHz / 1450MHz. The reason for the lower memory clocks for X1900 XT is unclear yet since the X1800XT is already clocked at 1.5GHz. It is also confirmed that R580 has 16 pipelines and 48 shader processors.

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