R580, the 48 pixel-shader processor version of the R520 (Radeon X1800), was announced this past January. R580 features a robust memory controller capable of utilizing several different types of memory, including GDDR4 which was not even available when the Radeon X1900 was first announced. Since then Hynix and Samsung have both jumped on the GDDR4 train with revenue shipments beginning several weeks ago. The new GDDR4 variants of R580-based Radeons are now called Radeon X1950. Radeon X1950 will retain all of the features of the Radeon X1900, and really only have the added benefit of a new cooler, GDDR4 memory and different frequency clocks.

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