Radeon HD 6990 vs Radeon R9 M390X

Intro

The Radeon HD 6990 makes use of a 40 nm design. AMD has set the core frequency at 830 MHz. The GDDR5 RAM works at a frequency of 1250 MHz on this particular model. It features 1536 SPUs along with 96 TAUs and 32 ROPs.

Compare those specifications to the Radeon R9 M390X, which comes with a GPU core clock speed of 723 MHz, and 4096 MB of GDDR5 memory set to run at 1250 MHz through a 256-bit bus. It also is made up of 2048 Stream Processors, 128 Texture Address Units, and 32 Raster Operation Units.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the maximum amount of information (in units of MB per second) that can be moved over the external memory interface in a second. It's worked out by multiplying the interface width by the speed of its memory. In the case of DDR RAM, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied per second. This figure is calculated by multiplying the total number of texture units by the core clock speed of the chip. The higher this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.

Pixel Rate: Pixel rate is the most pixels the graphics card could possibly record to the local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate also depends on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.