Radeon HD 4670 512MB vs Radeon HD 6670 (OEM)

Intro

The Radeon HD 4670 512MB comes with a clock frequency of 750 MHz and a GDDR4/GDDR3/DDR3/DDR2 memory frequency of 1000 MHz. It also features a 128-bit memory bus, and makes use of a 55 nm design. It is made up of 320(64x5) SPUs, 32 Texture Address Units, and 8 Raster Operation Units.

Compare all of that to the Radeon HD 6670 (OEM), which makes use of a 40 nm design. AMD has set the core speed at 800 MHz. The GDDR5 memory runs at a frequency of 1000 MHz on this particular model. It features 480 SPUs as well as 24 TAUs and 8 Rasterization Operator Units.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the largest amount of information (in units of MB per second) that can be transferred past the external memory interface in a second. It's calculated by multiplying the card's bus width by its memory speed. If it uses DDR RAM, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster 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 in one second. This figure is calculated by multiplying the total number of texture units of the card by the core clock speed of the chip. The higher the texel rate, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly write to the local memory in a 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 - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.