Radeon HD 7770 vs Radeon R9 M390X

Intro

Compare all of that to the Radeon R9 M390X, which comes with GPU core speed of 723 MHz, and 4096 MB of GDDR5 RAM set to run at 1250 MHz through a 256-bit bus. It also is made up of 2048 SPUs, 128 TAUs, and 32 Raster Operation Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7770		80 Watts
Radeon R9 M390X		125 Watts
	Difference: 45 Watts (56%)

Memory Bandwidth

In theory, the Radeon R9 M390X should be 122% quicker than the Radeon HD 7770 overall, because of its higher data rate. (explain)

Radeon R9 M390X		160000 MB/sec
Radeon HD 7770		72000 MB/sec
	Difference: 88000 (122%)

Texel Rate

The Radeon R9 M390X should be quite a bit (about 131%) better at texture filtering than the Radeon HD 7770. (explain)

Radeon R9 M390X		92544 Mtexels/sec
Radeon HD 7770		40000 Mtexels/sec
	Difference: 52544 (131%)

Pixel Rate

If running with a high resolution 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 7770		16000 Mpixels/sec
	Difference: 7136 (45%)

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 (counted in MB per second) that can be transferred across the external memory interface within a second. It is calculated by multiplying the card's bus width by its memory clock speed. If the card has DDR memory, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied per second. This 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 handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card could possibly write to the local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of colour ROPs by the the card's clock speed. 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 is also dependant on quite a few other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.