Radeon HD 4870 1GB vs Radeon HD 6670 (OEM)

Intro

The Radeon HD 4870 1GB comes with a clock frequency of 750 MHz and a GDDR5 memory speed of 900 MHz. It also makes use of a 256-bit bus, and uses a 55 nm design. It is comprised of 800(160x5) SPUs, 40 TAUs, and 16 ROPs.

Compare those specs to the Radeon HD 6670 (OEM), which features a core clock speed of 800 MHz and a GDDR5 memory frequency of 1000 MHz. It also features a 128-bit bus, and makes use of a 40 nm design. It is made up of 480 SPUs, 24 Texture Address Units, and 8 ROPs.

Price Comparison

Specifications

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

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed in one second. This number is worked out by multiplying the total amount of texture units by the core clock speed of the chip. The higher 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 that the graphics chip could possibly record to the local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of ROPs 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 quite a few other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the max fill rate.