GeForce GTX 660 vs Radeon HD 7950 3GB

Intro

Compare those specs to the Radeon HD 7950 3GB, which makes use of a 28 nm design. AMD has set the core frequency at 800 MHz. The GDDR5 memory runs at a speed of 1250 MHz on this particular model. It features 1792 SPUs along with 112 Texture Address Units and 32 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 660		140 Watts
Radeon HD 7950 3GB		200 Watts
	Difference: 60 Watts (43%)

Memory Bandwidth

In theory, the Radeon HD 7950 3GB should be much faster than the GeForce GTX 660 in general. (explain)

Radeon HD 7950 3GB		240000 MB/sec
GeForce GTX 660		144192 MB/sec
	Difference: 95808 (66%)

Texel Rate

The Radeon HD 7950 3GB should be a bit (approximately 14%) more effective at texture filtering than the GeForce GTX 660. (explain)

Radeon HD 7950 3GB		89600 Mtexels/sec
GeForce GTX 660		78400 Mtexels/sec
	Difference: 11200 (14%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 7950 3GB is a better choice, but not by far. (explain)

Radeon HD 7950 3GB		25600 Mpixels/sec
GeForce GTX 660		23520 Mpixels/sec
	Difference: 2080 (9%)

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 data (in units of megabytes per second) that can be transferred across the external memory interface in a second. The number is worked out by multiplying the card's bus width by its memory clock speed. If it uses DDR type memory, it should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

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

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