The History of the Modern Graphics Processor, Part 4: The Coming of General Purpose GPUs
Until the advent of DirectX 10, there was no point in adding undue complexity by enlarging the die area, which increased vertex shader functionality in addition to boosting the floating point precision of pixel shaders from 24-bit to 32-bit to match the requirement for vertex operations. With DX10's arrival, vertex and pixel shaders maintained a large level of common function, so moving to a unified shader arch eliminated a lot of unnecessary duplication of processing blocks. The first GPU to utilize this architecture was Nvidia's iconic G80.
Four years in development and $475 million produced a 681 million-transistor, 484mm² behemoth -- first as the 8800 GTX flagship and 8800 GTS 640MB on November 8. An overclocked GTX, the 8800 Ultra, represented the G80's pinnacle and was sandwiched between the launches of two lesser products: the 320MB GTS in February and the limited production GTS 640MB/112 Core on November 19, 2007.
Aided by the new Coverage Sample anti-aliasing (CSAA) algorithm, Nvidia saw its GTX demolish every single competitor in outright performance. Despite that success, the company dropped three percentage points in discrete graphics market share in the fourth quarter -- points AMD picked up on the strength of OEM contracts.
The Nvidia GeForce GTX 680 contains four GPCs with a total of eight SMXs, 1536 CUDA cores, eight geometry units, four raster units, 128 texture units, and 32 ROP units. The base clock is 1006MHz, the GTX 680 also carries 2GB of GDDR5 VRAM running at 6008MHz with a 256-bit interface providing 6.0Gb/s of throughput. Dual six-pin power connectors feed the card's TDP of 195W.
The HD 7950 has 2048 SPUs, 128 TAUs and 32 ROPs. The only other ports are on the I/O panel where you'll find a dual DL-DVI connector, a single HDMI 1.4a port, and two mini-DisplayPort 1.2 sockets. Supports a max resolution of 2560x1600 on up to 3 monitors.
Downloads and Drivers
From the Forums
Subscribe to TechSpot
Get free exclusive content, learn about new features and breaking tech news.