Radeon HD 6990 vs Radeon R9 M385X

Intro

Compare those specs to the Radeon R9 M385X, which makes use of a 28 nm design. AMD has clocked the core speed at 1100 MHz. The GDDR5 RAM is set to run at a speed of 1500 MHz on this particular card. It features 896 SPUs as well as 56 Texture Address Units and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

As far as performance goes, the Radeon HD 6990 should theoretically be much better than the Radeon R9 M385X in general. (explain)

Radeon HD 6990		320000 MB/sec
Radeon R9 M385X		96000 MB/sec
	Difference: 224000 (233%)

Texel Rate

The Radeon HD 6990 will be much (more or less 159%) more effective at AF than the Radeon R9 M385X. (explain)

Radeon HD 6990		159360 Mtexels/sec
Radeon R9 M385X		61600 Mtexels/sec
	Difference: 97760 (159%)

Pixel Rate

The Radeon HD 6990 should be a lot (more or less 202%) better at FSAA than the Radeon R9 M385X, and should be able to handle higher screen resolutions more effectively. (explain)

Radeon HD 6990		53120 Mpixels/sec
Radeon R9 M385X		17600 Mpixels/sec
	Difference: 35520 (202%)

Please note that the above 'benchmarks' are all just theoretical - the results were calculated based on the card's specifications, and real-world performance may (and probably will) vary at least a bit.

One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.

Price Comparison

Specifications

Memory Bandwidth: Bandwidth is the maximum amount of data (counted in MB per second) that can be transported over the external memory interface within a second. It's worked out by multiplying the card's bus width by its memory clock speed. In the case of DDR memory, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range 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 calculated by multiplying the total texture units of the card by the core clock speed of the chip. The higher this number, the better the graphics 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 could possibly record to its local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the number of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on quite a few other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.