Radeon HD 6990 vs Radeon R9 M275X

Intro

Compare those specifications to the Radeon R9 M275X, which comes with core speeds of 900 MHz on the GPU, and 1125 MHz on the 2048 MB of GDDR5 RAM. It features 640 SPUs along with 40 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon R9 M275X		50 Watts
Radeon HD 6990		375 Watts
	Difference: 325 Watts (650%)

Memory Bandwidth

Performance-wise, the Radeon HD 6990 should theoretically be quite a bit superior to the Radeon R9 M275X overall. (explain)

Radeon HD 6990		320000 MB/sec
Radeon R9 M275X		72000 MB/sec
	Difference: 248000 (344%)

Texel Rate

The Radeon HD 6990 is quite a bit (about 343%) better at anisotropic filtering than the Radeon R9 M275X. (explain)

Radeon HD 6990		159360 Mtexels/sec
Radeon R9 M275X		36000 Mtexels/sec
	Difference: 123360 (343%)

Pixel Rate

The Radeon HD 6990 is quite a bit (about 269%) more effective at anti-aliasing than the Radeon R9 M275X, and should be able to handle higher resolutions better. (explain)

Radeon HD 6990		53120 Mpixels/sec
Radeon R9 M275X		14400 Mpixels/sec
	Difference: 38720 (269%)

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 megabytes per second) that can be transferred over the external memory interface in a second. It is calculated by multiplying the bus width by its memory speed. If it uses DDR memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed per second. This number is calculated by multiplying the total number of texture units of the card by the core clock 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 in one second.

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