Radeon HD 4790 vs Radeon R9 M280X

Intro

Compare those specifications to the Radeon R9 M280X, which uses a 28 nm design. AMD has clocked the core frequency at 900 MHz. The GDDR5 RAM runs at a frequency of 1375 MHz on this particular model. It features 896 SPUs along with 56 Texture Address Units and 16 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Memory Bandwidth

In theory, the Radeon HD 4790 will be 16% quicker than the Radeon R9 M280X overall, because of its higher bandwidth. (explain)

Radeon HD 4790		102400 MB/sec
Radeon R9 M280X		88000 MB/sec
	Difference: 14400 (16%)

Texel Rate

The Radeon R9 M280X will be quite a bit (more or less 163%) more effective at anisotropic filtering than the Radeon HD 4790. (explain)

Radeon R9 M280X		50400 Mtexels/sec
Radeon HD 4790		19200 Mtexels/sec
	Difference: 31200 (163%)

Pixel Rate

The Radeon R9 M280X is much (about 50%) better at full screen anti-aliasing than the Radeon HD 4790, and also will be capable of handling higher screen resolutions better. (explain)

Radeon R9 M280X		14400 Mpixels/sec
Radeon HD 4790		9600 Mpixels/sec
	Difference: 4800 (50%)

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 maximum amount of data (measured in MB per second) that can be transported over the external memory interface in a second. The number is worked out by multiplying the bus width by its memory speed. If the card has DDR type memory, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed in one second. This number is calculated by multiplying the total amount of texture units by the core clock speed of the chip. The better this number, the better the video 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 number of pixels that the graphics chip can possibly write to the local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the amount of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate also depends on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.