Radeon HD 6990 vs Radeon R9 M385X

Intro

Compare all that to the Radeon R9 M385X, which features a clock speed of 1100 MHz and a GDDR5 memory speed of 1500 MHz. It also uses a 128-bit memory bus, and makes use of a 28 nm design. It features 896 SPUs, 56 TAUs, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

The Radeon HD 6990 should theoretically be a lot faster than the Radeon R9 M385X overall. (explain)

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

Texel Rate

The Radeon HD 6990 should be much (about 159%) faster with regards to AF than the Radeon R9 M385X. (explain)

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

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 6990 is the winner, by far. (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 largest amount of information (measured in MB per second) that can be moved past the external memory interface in a second. The number is worked out by multiplying the card's interface width by its memory clock speed. In the case of DDR type memory, it should be multiplied by 2 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 texture map elements (texels) that can be applied per second. This is calculated by multiplying the total number of texture units by the core speed of the chip. The better the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.

Pixel Rate: Pixel rate is the most pixels the graphics card can possibly write to the local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the number of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate also depends on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.