GeForce GTX 660 vs Radeon R9 M385X

Intro

Compare that to the Radeon R9 M385X, which has core speeds of 1100 MHz on the GPU, and 1500 MHz on the 4096 MB of GDDR5 memory. It features 896 SPUs as well as 56 TAUs and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Theoretically speaking, the GeForce GTX 660 will be 50% quicker than the Radeon R9 M385X in general, due to its greater bandwidth. (explain)

GeForce GTX 660		144192 MB/sec
Radeon R9 M385X		96000 MB/sec
	Difference: 48192 (50%)

Texel Rate

The GeForce GTX 660 should be much (more or less 27%) faster with regards to anisotropic filtering than the Radeon R9 M385X. (explain)

GeForce GTX 660		78400 Mtexels/sec
Radeon R9 M385X		61600 Mtexels/sec
	Difference: 16800 (27%)

Pixel Rate

The GeForce GTX 660 will be quite a bit (about 34%) faster with regards to FSAA than the Radeon R9 M385X, and also will be able to handle higher screen resolutions more effectively. (explain)

GeForce GTX 660		23520 Mpixels/sec
Radeon R9 M385X		17600 Mpixels/sec
	Difference: 5920 (34%)

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 largest amount of information (measured in megabytes per second) that can be transported over the external memory interface within a second. The number is calculated by multiplying the card's interface width by its memory speed. In the case of DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied in one second. This number is worked out by multiplying the total amount of texture units of the card by the core 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 in a second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly write to its local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.