Thursday, March 23, 2000

Introduction The Abit Siluro GF256 graphics card stands as the head of Abit's graphics card family. Gifted with the new Nvidia GeForce 256 GPU (Graphic Processing Unit) using a bandwidth of 256-bit and a Ramdac at an operating at a frequency of 350Mhz, the GF256 utilizes no less than 32MB of SDRAM memory, clocked at 166Mhz, with the core graphics engine clocked at 120MHz. This new generation of graphics processors supports "Transform and Lighting", "Cube Environment Mapping", and many other functionalities that are unheard of by other graphic cards.

Below, a synopsis of the principal features supported by the GF256:

The particularities

To be brief, the principal distinction between the GF256, and other graphics cards that implement the same GeForce chip, is the GF256's support for a flat-panel connector.

What characterizes the GeForce 256 chipset is principally the QuadPipe architecture, each pipeline which manifests as a 64-bit wide bus. With each pipeline using 64-bit data paths, each is able to render 4 pixels in 32-bit color per clock cycle; double the performance of the TNT2. To compare with the TNT2 chipset, the GeForce 256 GPU is capable of producing 480Mpixels/sec, compared to the 300Mpixels/sec performance of the TNT2. This advantage stems wholly from the GeForce's ability to process 4 pixels per cycle in a simple textured environment. In reality, though, this situation rarely occurs, as the majority of games sport multiple textures. In that case, it's not 4, but 2 textures per multitextured pixel that's generated. Some may be a bit disquieted by the fact that the GeForce 256 GPU runs along at 120MHz, but in fact the advantage of the QuadPipe architecture offers no less than 1.6 times the bandwidth of the TNT2.

As for the memory system, the GeForce 256 uses a 128-bit bus in combination with 5ns (200MHz) memory. However, when it came time to ship, Abit decided to set the speed of the memory bus to 166MHz, but fortunately it is quite possible to tweak this a little, as it is still quite possible for this memory to run comfortably at 200MHz.

Next: Transform & Lighting.

Technical Specifications