Radeon HD 7870 vs Radeon HD 7950 3GB

Intro

The Radeon HD 7870 comes with a core clock speed of 1000 MHz and a GDDR5 memory speed of 1200 MHz. It also uses a 256-bit memory bus, and makes use of a 28 nm design. It is made up of 1280 SPUs, 80 TAUs, and 32 ROPs.

Compare those specifications to the Radeon HD 7950 3GB, which has core clock speeds of 800 MHz on the GPU, and 1250 MHz on the 3072 MB of GDDR5 memory. It features 1792 SPUs along with 112 TAUs and 32 Rasterization Operator Units.

Price Comparison

Specifications

Memory Bandwidth: Bandwidth is the largest amount of data (in units of megabytes per second) that can be transferred over the external memory interface in one second. It's calculated by multiplying the interface width by its memory clock speed. If the card has DDR type RAM, it should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the better 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 can be processed per second. This number is calculated by multiplying the total number of texture units of the card by the core clock speed of the chip. The higher this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.

Pixel Rate: Pixel rate is the maximum amount of pixels the video card can possibly write to its local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.