GeForce GTX 660 vs Radeon R5 M255

Intro

Compare those specifications to the Radeon R5 M255, which has core speeds of 940 MHz on the GPU, and 1000 MHz on the 2048 MB of DDR3 memory. It features 320 SPUs as well as 20 TAUs and 8 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Theoretically speaking, the GeForce GTX 660 will be 801% faster than the Radeon R5 M255 overall, because of its greater data rate. (explain)

GeForce GTX 660		144192 MB/sec
Radeon R5 M255		16000 MB/sec
	Difference: 128192 (801%)

Texel Rate

The GeForce GTX 660 will be much (approximately 317%) better at texture filtering than the Radeon R5 M255. (explain)

GeForce GTX 660		78400 Mtexels/sec
Radeon R5 M255		18800 Mtexels/sec
	Difference: 59600 (317%)

Pixel Rate

The GeForce GTX 660 will be much (more or less 213%) better at FSAA than the Radeon R5 M255, and also should be able to handle higher screen resolutions more effectively. (explain)

GeForce GTX 660		23520 Mpixels/sec
Radeon R5 M255		7520 Mpixels/sec
	Difference: 16000 (213%)

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 information (measured in MB per second) that can be moved over the external memory interface within a second. The number is worked out by multiplying the interface width by its memory speed. In the case of DDR memory, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better 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 are applied per second. This number is worked out 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 most pixels that the graphics chip could possibly record to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the max fill rate.