As its R4xx codename implies, R480 isn’t ATI’s next generation graphics product. Instead, R480 relies on the same underlying features as the original RADEON X800 family. This includes ATI’s SMARTSHADER HD shaders (marketing speak for shader model 2.0b), a 16-pixel pipline architecture on “XT” parts while the “PRO” line gets 12 pixel pipes, 6 vertex pipelines, SMOOTHVISION HD with temporal AA support, 3Dc, and of course, the 256-bit memory interface that is responsible for keeping the graphics core fed with data.
The only change that has been made is the clock speeds. The RADEON X850 XT Platinum Edition features a 540MHz core with 590MHz memory (1.18GHz effective) while the RADEON X850 XT sports a 520MHz graphics core and is outfitted with 540MHz memory (1.08GHz effective). Both of these chips feature 16 pixel pipes and ship with 256MB of memory, so the new clocks should allow the X850 XT PE to outperform the RADEON X800 XT Platinum Edition, while the X850 XT vanilla should finish a hair behind the X800 XT PE, which featured a 520MHz core with its memory running at a slightly faster 560MHz.
R480 is based on TSMC’s 0.13-micron manufacturing process with copper interconnects and low-k dielectric material, just like the R420/R423 found in X800, only ATI and TSMC have been working together to optimize the graphics core for operation at higher clock speeds. ATI also added the same dynamic clock gating that is found in their mobile graphics line for improved power consumption. If you recall, this allows ATI to turn off portions of the chip that aren’t being used, say for instance when you’re in 2D mode reading this webpage. This significantly reduces thermal output. The new design was then respun and paired with faster GDDR3 memory.
Rounding out the R480 line is RADEON X850 PRO. This chip features a 12-pixel pipeline architecture running at approximately 520MHz (we’ve been told that the final number may be a little higher or lower), while its memory runs at 540MHz.
R430 is nothing more than the R420/R423 core found in RADEON X800 shrunk down to TSMC’s 0.11-micron manufacturing process. 0.11-micron doesn’t feature all the high tech goodies of 0.13-micron such as low-k, instead 0.11-micron is used to allow ATI to yield more chips per silicon wafer. This in turn lowers manufacturing costs, assuming good yields. To help ensure that this occurs, ATI has toned down the clock speeds on R430 to 400MHz.
Two SKUs are based on R430 technology: the RADEON X800 XL and the RADEON X800. The X800 XL features a 16-pixel pipeline architecture running at 400MHz with 256MB of memory operating at 500MHz (1.0GHz effective). The RADEON X800 also sports a 400MHz graphics core, only the number of pixel pipelines have been reduced down to 12. Running alongside the X800’s graphics core is 128MB of memory running at 350MHz (700MHz effective).
While the reduced clocks may come somewhat as a disappointment, the price tag on R430 won’t. The X800 XL will retail for $349, while the X800 will sell for $249. In addition, neither card requires an external power connection.