We took the Gigabyte GV-NX88S640H-RH graphics card - based on the NVIDIA GeForce 8800 GTS graphics processing unit (GPU) - for a spin to see how it compares to cards based on the more powerful GeForce 8800 GTX and the older 7900 GTX GPUs.

Pixel Processing Power

There are two GPUs from NVIDIA in the GeForce 8 series: the 8800 GTS that this card is based upon and the more powerful 8800 GTX. The GeForce 8800 (also often referred to as the G80) architecture offers two key improvements over previous generations. The first is a move to support DirectX 10, which will make its debut with the release of Windows Vista, and support for Shader Model 4.0 along side that. But NVIDIA's biggest innovation comes in the form of a unified GPU (graphics processor unit) architecture, which effectively revolutionises the way graphics cards process data and subsequently what they are capable of producing on-screen.

The days of fixed pixel and vertex shaders are almost gone. To accommodate the new Direct X 10 application programming interface (API), the 8800 GPU implements a unified shader architecture. Unlike previous generations the unified architecture utilises stream processors that can be dynamically allocated to process pixel, geometry or vertex shading tasks. As any of these stream processors can pick up the slack, the ability of the card to render scenes heavily geared towards one type of shading or another is no longer restricted by the number of shaders fixed to do that task, as it was with the last generation. This architecture is a giant leap ahead of anything else, including the massive 48 pixel shader design of some of the ATI Radeon X1900 cards and should give game developers more leeway create realism and complexity on screen.

As ATI's DirectX 10 ready GPU (codenamed the R600) is still not likely to appear until early 2007, the 8800 GPU from NVIDIA is currently the hottest piece of gaming hardware available. Microsoft's DirectX 10 API and Shader Model 4.0 offer some new features including support for the aforementioned geometry shaders, allowing game developers to ramp up the complexity of game graphics. But DirectX 10 also refines communication between software and hardware, and aims to reduce overheads, creating a more efficient use of overall resources. Initially this should mean games will run smoother. Eventually, however, this improved efficiency should create headroom for developers to push the limits of your graphics card by allocating more tasks to the GPU, resulting in more spectacular gaming environments. While there are currently no games available that use DirectX 10 and won't be for some time, highly awaited titles such as Crysis from Crytek (the makers of FarCry) are already looking to utilise its features.

The core speed of 500MHz doesn't immediately sound impressive, but the new architecture means this is still a superior card to everything bar those cards running the GeForce 8800 GTX. With 96 stream processors clocked at 1200MHz it should handle any shading your computer can throw at it. Similarly, the 640MB of 800MHz (1600MHz) GDDR3 RAM doesn't sound that much more impressive than the Radeon X1950XTX's 512MB of 1GHz (2000MHz) GDDR4 memory. But the 8800 GTS utilises a beefy 320-bit memory controller, which gives it an impressive 64GB/sec throughput, on par with the X1950 XTX.

In all benchmarks we ran on our new testbed (Intel QX6700 Quad Core CPU, a 10,000rpm 150GB Western Digital hard drive and 1GB of DDR2 800MHz RAM from Corsair, Gigabyte GA-965P-DQ6 Version 2 motherboard and a Seasonic S12 Energy+ SS-650HT 650 Watt power supply) it scored well. We ran it through 3DMark 2006 at 1280 x 1024 with 8x AA (anti-aliasing) and 16x AF (anisotropic filtering) and it scored 5795. At 1680 x 1050 it scored 4620. Furthermore this is the first NVIDIA GPU capable of using anti-aliasing in scenes with high dynamic range lighting (HDR), so older generation NVIDIA cards could not even complete this test.

The GV-NX88S640H-RH returned a result under the FEAR test when running at 1280x960 at high detail with 16x AF and 4x AA of 81 frames per second (fps). This compared favourably to the which returned a result of 68fps, however the 8800 GTX-based from Asus scored a whopping 107fps. In Quake 4 it was much the same averaging 161.5 fps at 1280 x 1024, 4xAA and high quality settings; 22.5fps better than the but 18.2fps below the . This places this card smack in the middle for performance under FEAR between the two GPUs immediately above and below it in the NVIDIA line.

The board itself is the largest gaming board we've seen. Not only is it longer than many motherboards are wide, but with the heat sink and fan it takes up the space of two PCI slots, limiting the other devices you can fit into the case. Unlike the 8800 GTX from Asus this card only needs one PCI-e power cable plugged in.