Two GPUs, one card: A review of the ATI Radeon HD 3870 X2
ATI and NVIDIA have struggled to out-do each other in the video card performance wars ever since ATI launched the original Radeon in 2000, but the red team has spent most of the last 18 months dealing from a very bad deck. The company's R600-based HD 2000 series was ultimately unable to challenge NVIDIA at the high end of the market, so G80-based GeForce products dominated the enthusiast market through the first three quarters of 2007.
Last November, ATI unveiled its improved RV670 GPU and launched a new line of video cards around the chip. The RV670 GPU was an architectural tweak of the R600 (rather than a new design), but building the chip on a smaller process allowed ATI to dramatically reduce total power consumption and improve the GPU's performance-per-watt. Moving from a 512-bit memory bus on the R600 to a 256-bit memory bus on the RV670 also reduced the GPU's die size, further cutting manufacturing costs.
