GeForce GTX 580 3GB vs Radeon HD 4890 1GB

Intro

The GeForce GTX 580 3GB features a core clock speed of 772 MHz and a GDDR5 memory speed of 1002 MHz. It also uses a 384-bit memory bus, and uses a 40 nm design. It features 512 SPUs, 64 Texture Address Units, and 48 Raster Operation Units.

Compare those specs to the Radeon HD 4890 1GB, which comes with 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 TAUs and 16 ROPs.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the max amount of information (in units of MB per second) that can be transferred over the external memory interface in one second. It is worked out by multiplying the interface width by the speed of its memory. In the case of DDR memory, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the most pixels that the graphics chip can possibly record to its local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the amount of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the max fill rate.