Radeon HD 6790 vs Radeon R9 M390X

Intro

Compare all of that to the Radeon R9 M390X, which uses a 28 nm design. AMD has set the core speed at 723 MHz. The GDDR5 memory works at a frequency of 1250 MHz on this specific model. It features 2048 SPUs along with 128 TAUs and 32 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon R9 M390X		125 Watts
Radeon HD 6790		150 Watts
	Difference: 25 Watts (20%)

Memory Bandwidth

In theory, the Radeon R9 M390X will be 19% quicker than the Radeon HD 6790 overall, because of its greater data rate. (explain)

Radeon R9 M390X		160000 MB/sec
Radeon HD 6790		134400 MB/sec
	Difference: 25600 (19%)

Texel Rate

The Radeon R9 M390X is quite a bit (about 175%) faster with regards to texture filtering than the Radeon HD 6790. (explain)

Radeon R9 M390X		92544 Mtexels/sec
Radeon HD 6790		33600 Mtexels/sec
	Difference: 58944 (175%)

Pixel Rate

If using lots of anti-aliasing is important to you, then the Radeon R9 M390X is the winner, and very much so. (explain)

Radeon R9 M390X		23136 Mpixels/sec
Radeon HD 6790		13440 Mpixels/sec
	Difference: 9696 (72%)

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 data (measured in megabytes per second) that can be transported past the external memory interface within a second. The number is worked out by multiplying the bus width by the speed of its memory. If the card has DDR type RAM, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the bandwidth is, 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 can be processed per second. This figure is calculated by multiplying the total texture units by the core clock speed of the chip. The higher this number, 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 amount of pixels the graphics card can possibly record to the local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends 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.