GeForce GTX 660 vs Radeon R9 M385X

Intro

Compare those specifications to the Radeon R9 M385X, which comes with a core clock speed of 1100 MHz and a GDDR5 memory speed of 1500 MHz. It also features a 128-bit memory bus, and makes use of a 28 nm design. It features 896 SPUs, 56 Texture Address Units, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

As far as performance goes, the GeForce GTX 660 should in theory be much superior to the Radeon R9 M385X in general. (explain)

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

Texel Rate

The GeForce GTX 660 should be a lot (about 27%) more effective at texture 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 is quite a bit (more or less 34%) more effective at full screen anti-aliasing than the Radeon R9 M385X, and capable of handling higher screen resolutions without slowing down too much. (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: Bandwidth is the largest amount of information (measured in MB per second) that can be transferred past the external memory interface within a second. The number is calculated by multiplying the card's interface width by its memory speed. If the card has DDR type memory, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

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

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card could possibly record to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the number 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 filling the screen with pixels (the image). The actual pixel rate is also dependant on lots of other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.