Radeon HD 6990 vs Radeon R9 M385X

Intro

Compare that to the Radeon R9 M385X, which comes with a GPU core clock speed of 1100 MHz, and 4096 MB of GDDR5 RAM set to run at 1500 MHz through a 128-bit bus. It also is comprised of 896 Stream Processors, 56 Texture Address Units, and 16 Raster Operation Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Memory Bandwidth

In theory, the Radeon HD 6990 should perform a lot faster 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 is a lot (approximately 159%) better 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 is a lot (more or less 202%) faster with regards to AA than the Radeon R9 M385X, and 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: Memory bandwidth is the largest amount of data (measured in MB per second) that can be transported past the external memory interface in a second. The number is calculated by multiplying the interface width by the speed of its memory. If the card has DDR RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the 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 are applied in one second. This is calculated by multiplying the total number of texture units of the card by the core speed of the chip. The higher the texel rate, 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 card can possibly write to its local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the number of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on lots of other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.