AMD Delivers World’s First TeraFLOPS Graphics Chip 

ATI Radeon HD 4870 introduces GDDR5 performance, pushes 1.2 teraFLOPS
The ATI Radeon HD 4870, available immediately represents an unprecedented 1.2 teraFLOPS of visual compute power. It features a stock GPU core clock speed of 750 MHz, 512 MB of GDDR5 memory rated at 3.6 gigabits/second, and comes in a dual-slot PCI Express 2.0 configuration with a maximum board power of 160 watts.

ATI Radeon HD 4850: one teraFLOPS of visual compute power
The ATI Radeon HD 4850, immediately available received an enthusiastic welcome from global graphics reviewers. The ATI Radeon HD 4850 is the world’s first teraFLOPS graphics chip, with 800 stream processing cores (identical to the ATI Radeon HD 4870), a stock GPU core clock speed of 625 MHz, 512 MB of GDDR3 memory rated at 2 gigabits/second, and comes in a single-slot PCI Express 2.0 configuration with a maximum board power of 110 watts.

It wasn't long ago that global climate models were created with mainframes comprised of hundreds of CPU's and today all you need is a quad-core Opteron or Phenom and two ATI Radeon HD 4870 running in CrossfireX