Radeon HD 4870 2GB vs Radeon R9 380 4G

Intro

The Radeon HD 4870 2GB comes with clock speeds of 750 MHz on the GPU, and 900 MHz on the 2048 MB of GDDR5 memory. It features 800(160x5) SPUs as well as 40 TAUs and 16 Rasterization Operator Units.

Compare those specifications to the Radeon R9 380 4G, which features a GPU core clock speed of 970 MHz, and 4096 MB of GDDR5 RAM set to run at 1425 MHz through a 256-bit bus. It also is made up of 1792 Stream Processors, 112 Texture Address Units, and 32 Raster Operation Units.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the largest amount of information (counted in MB per second) that can be moved past the external memory interface in a second. It's worked out by multiplying the bus width by the speed of its memory. If it uses DDR type RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied in one second. This figure is worked out by multiplying the total texture units by the core 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 applied in a second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly record to the local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of ROPs 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 fill rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.