GeForce GTX 660 vs Radeon HD 5850

Intro

The GeForce GTX 660 comes with core speeds of 980 MHz on the GPU, and 1502 MHz on the 2048 MB of GDDR5 memory. It features 960 SPUs along with 80 Texture Address Units and 24 Rasterization Operator Units.

Compare all that to the Radeon HD 5850, which has GPU core speed of 725 MHz, and 1024 MB of GDDR5 RAM set to run at 1000 MHz through a 256-bit bus. It also is comprised of 1440(288x5) SPUs, 72 Texture Address Units, and 32 Raster Operation Units.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the maximum amount of information (counted in megabytes per second) that can be transferred across the external memory interface within a second. It is calculated by multiplying the card's interface width by its memory clock speed. In the case of DDR memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed per second. This is worked out by multiplying the total texture units of the card by the core speed of the chip. The better the texel rate, the better the 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 can possibly record to its local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the number of ROPs by the clock 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 quite a few other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.