Radeon HD 6870 vs Radeon R9 M275X

Intro

Compare those specs to the Radeon R9 M275X, which comes with clock speeds of 900 MHz on the GPU, and 1125 MHz on the 2048 MB of GDDR5 RAM. It features 640 SPUs along with 40 TAUs and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon R9 M275X		50 Watts
Radeon HD 6870		151 Watts
	Difference: 101 Watts (202%)

Memory Bandwidth

In theory, the Radeon HD 6870 will be 87% quicker than the Radeon R9 M275X overall, due to its greater bandwidth. (explain)

Radeon HD 6870		134400 MB/sec
Radeon R9 M275X		72000 MB/sec
	Difference: 62400 (87%)

Texel Rate

The Radeon HD 6870 is quite a bit (about 40%) more effective at texture filtering than the Radeon R9 M275X. (explain)

Radeon HD 6870		50400 Mtexels/sec
Radeon R9 M275X		36000 Mtexels/sec
	Difference: 14400 (40%)

Pixel Rate

If using lots of anti-aliasing is important to you, then the Radeon HD 6870 is a better choice, by far. (explain)

Radeon HD 6870		28800 Mpixels/sec
Radeon R9 M275X		14400 Mpixels/sec
	Difference: 14400 (100%)

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.

Price Comparison

Specifications

Memory Bandwidth: Bandwidth is the largest amount of information (in units of MB per second) that can be moved over the external memory interface in a second. The number is worked out by multiplying the card's interface width by the speed of its memory. In the case of DDR type RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, 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 number of texture map elements (texels) that are applied in one second. This figure is worked out by multiplying the total texture units by the core speed of the chip. The better the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.