GeForce GTX 660 Ti vs Radeon R9 M390X

Intro

Compare those specs to the Radeon R9 M390X, which features a core clock speed of 723 MHz and a GDDR5 memory speed of 1250 MHz. It also features a 256-bit memory bus, and uses a 28 nm design. It is made up of 2048 SPUs, 128 Texture Address Units, and 32 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon R9 M390X		125 Watts
GeForce GTX 660 Ti		150 Watts
	Difference: 25 Watts (20%)

Memory Bandwidth

In theory, the Radeon R9 M390X should be a little bit faster than the GeForce GTX 660 Ti overall. (explain)

Radeon R9 M390X		160000 MB/sec
GeForce GTX 660 Ti		144000 MB/sec
	Difference: 16000 (11%)

Texel Rate

The GeForce GTX 660 Ti should be a little bit (more or less 11%) better at texture filtering than the Radeon R9 M390X. (explain)

GeForce GTX 660 Ti		102480 Mtexels/sec
Radeon R9 M390X		92544 Mtexels/sec
	Difference: 9936 (11%)

Pixel Rate

The Radeon R9 M390X should be a little bit (approximately 5%) better at AA than the GeForce GTX 660 Ti, and also should be capable of handling higher resolutions more effectively. (explain)

Radeon R9 M390X		23136 Mpixels/sec
GeForce GTX 660 Ti		21960 Mpixels/sec
	Difference: 1176 (5%)

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 max amount of data (counted in megabytes per second) that can be transported over the external memory interface in one second. It is calculated by multiplying the interface width by the speed of its memory. If the card has DDR memory, the result should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.

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

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card could possibly write to the local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.