GeForce 8800 GTX vs Radeon HD 3870 1GB

Intro

The GeForce 8800 GTX makes use of a 90 nm design. nVidia has clocked the core speed at 575 MHz. The GDDR3 RAM is set to run at a frequency of 900 MHz on this particular model. It features 128 SPUs as well as 64 Texture Address Units and 24 Rasterization Operator Units.

Compare those specs to the Radeon HD 3870 1GB, which comes with a clock speed of 775 MHz and a GDDR4 memory frequency of 1125 MHz. It also features a 256-bit memory bus, and makes use of a 55 nm design. It is made up of 320(64x5) SPUs, 16 Texture Address Units, and 16 ROPs.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the maximum amount of information (measured in megabytes per second) that can be transported across the external memory interface in a second. The number is calculated by multiplying the card's interface width by its memory clock speed. If the card has DDR memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

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

Pixel Rate: Pixel rate is the most pixels that the graphics card could possibly write to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the number of colour ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.