Radeon HD 6790 vs Radeon R5 M255

Intro

Compare all of that to the Radeon R5 M255, which has GPU core speed of 940 MHz, and 2048 MB of DDR3 memory set to run at 1000 MHz through a 64-bit bus. It also is made up of 320 SPUs, 20 TAUs, and 8 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Performance-wise, the Radeon HD 6790 should in theory be much superior to the Radeon R5 M255 in general. (explain)

Radeon HD 6790		134400 MB/sec
Radeon R5 M255		16000 MB/sec
	Difference: 118400 (740%)

Texel Rate

The Radeon HD 6790 should be quite a bit (about 79%) more effective at anisotropic filtering than the Radeon R5 M255. (explain)

Radeon HD 6790		33600 Mtexels/sec
Radeon R5 M255		18800 Mtexels/sec
	Difference: 14800 (79%)

Pixel Rate

If using a high screen resolution is important to you, then the Radeon HD 6790 is a better choice, by far. (explain)

Radeon HD 6790		13440 Mpixels/sec
Radeon R5 M255		7520 Mpixels/sec
	Difference: 5920 (79%)

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 information (counted in MB per second) that can be transported across the external memory interface in a second. The number is worked out by multiplying the bus width by the speed of its memory. If it uses 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 anti-aliasing, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied per second. This is calculated by multiplying the total amount of texture units by the core speed of the chip. The better the texel rate, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly write to its local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the number of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - aka 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 potential to reach the maximum fill rate.