GeForce 8800 Ultra vs Radeon HD 4890 1GB

Intro

The GeForce 8800 Ultra features a core clock frequency of 612 MHz and a GDDR3 memory frequency of 1080 MHz. It also makes use of a 384-bit memory bus, and makes use of a 90 nm design. It is comprised of 128 SPUs, 64 Texture Address Units, and 24 Raster Operation Units.

Compare all of that to the Radeon HD 4890 1GB, which features core clock speeds of 1000 MHz on the GPU, and 975 MHz on the 1024 MB of GDDR5 memory. It features 800(160x5) SPUs as well as 40 Texture Address Units and 16 Rasterization Operator Units.

Price Comparison

Specifications

Memory Bandwidth: Bandwidth is the maximum amount of information (in units of MB per second) that can be transported past the external memory interface in a second. It's worked out by multiplying the interface width by its memory clock speed. If it uses DDR type RAM, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied per second. This is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The higher this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card can possibly record to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.