"ATI is preparing a R420 AGP swizzle stick for Q2 this year. Cards will use GDDR 2 memory 256MB at 256 bits. It's possible to use 128 implementations as well. This chip be able to support DDR, DDR2 and GDDR3 so whenever it's ready ATI can make it work with its current memory controller. They will of course use 8x32MB chips."
Del med dine venner