Radeon HD 4850 X2 512MB vs Radeon HD 5750 1GB

Intro

The Radeon HD 4850 X2 512MB comes with a core clock frequency of 625 MHz and a GDDR3 memory frequency of 993 MHz. It also makes use of a 256-bit memory bus, and makes use of a 55 nm design. It features 800(160x5) SPUs, 40 Texture Address Units, and 16 Raster Operation Units.

Compare those specifications to the Radeon HD 5750 1GB, which uses a 40 nm design. AMD has clocked the core frequency at 700 MHz. The GDDR5 memory works at a frequency of 1150 MHz on this particular card. It features 720(144x5) SPUs along with 36 Texture Address Units and 16 Rasterization Operator Units.

Price Comparison

Specifications

Memory Bandwidth: Bandwidth is the largest amount of information (counted in megabytes per second) that can be transferred past the external memory interface in one second. It's calculated by multiplying the card's interface width by its memory clock speed. If the card has DDR RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.

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

Pixel Rate: Pixel rate is the most pixels the video card could possibly record to its local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Raster Operations Pipelines by the the card's clock speed. 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 lots of other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.