Radeon HD 7970 vs Radeon R9 M390X

Intro

Compare all that to the Radeon R9 M390X, which comes with a clock frequency of 723 MHz and a GDDR5 memory speed of 1250 MHz. It also uses a 256-bit memory bus, and makes use of a 28 nm design. It is comprised of 2048 SPUs, 128 Texture Address Units, and 32 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon R9 M390X		125 Watts
Radeon HD 7970		250 Watts
	Difference: 125 Watts (100%)

Memory Bandwidth

Performance-wise, the Radeon HD 7970 should theoretically be quite a bit superior to the Radeon R9 M390X overall. (explain)

Radeon HD 7970		264000 MB/sec
Radeon R9 M390X		160000 MB/sec
	Difference: 104000 (65%)

Texel Rate

The Radeon HD 7970 should be much (approximately 28%) better at anisotropic filtering than the Radeon R9 M390X. (explain)

Radeon HD 7970		118400 Mtexels/sec
Radeon R9 M390X		92544 Mtexels/sec
	Difference: 25856 (28%)

Pixel Rate

If running with high levels of AA is important to you, then the Radeon HD 7970 is the winner, by far. (explain)

Radeon HD 7970		29600 Mpixels/sec
Radeon R9 M390X		23136 Mpixels/sec
	Difference: 6464 (28%)

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: Memory bandwidth is the maximum amount of information (counted in MB per second) that can be moved across the external memory interface within a second. The number is worked out by multiplying the card's bus width by the speed of its memory. If it uses DDR memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied in one second. This is calculated by multiplying the total amount of texture units of the card by the core clock speed of the chip. The better this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.

Pixel Rate: Pixel rate is the most pixels the video card can possibly write to the local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.