GeForce GTX 870M vs Radeon R5 M255

Intro

Compare all of that to the Radeon R5 M255, which uses a 28 nm design. AMD has clocked the core frequency at 940 MHz. The DDR3 RAM runs at a frequency of 1000 MHz on this particular model. It features 320 SPUs along with 20 Texture Address Units and 8 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

In theory, the GeForce GTX 870M will be 500% faster than the Radeon R5 M255 overall, due to its greater data rate. (explain)

GeForce GTX 870M		96000 MB/sec
Radeon R5 M255		16000 MB/sec
	Difference: 80000 (500%)

Texel Rate

The GeForce GTX 870M should be a lot (approximately 461%) more effective at anisotropic filtering than the Radeon R5 M255. (explain)

GeForce GTX 870M		105392 Mtexels/sec
Radeon R5 M255		18800 Mtexels/sec
	Difference: 86592 (461%)

Pixel Rate

If using lots of anti-aliasing is important to you, then the GeForce GTX 870M is superior to the Radeon R5 M255, by far. (explain)

GeForce GTX 870M		22584 Mpixels/sec
Radeon R5 M255		7520 Mpixels/sec
	Difference: 15064 (200%)

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 moved past the external memory interface in one second. It is calculated by multiplying the card's bus width by its memory clock speed. If it uses DDR 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 high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied in one second. This number is calculated by multiplying the total texture units of the card by the core clock speed of the chip. The better the texel rate, 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 number of pixels the graphics card can possibly write to the local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the number of Raster Operations Pipelines by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.