Geforce GTX 680 vs Radeon HD 7950 3GB

Intro

Compare all of that to the Radeon HD 7950 3GB, which comes with a clock frequency of 800 MHz and a GDDR5 memory speed of 1250 MHz. It also uses a 384-bit bus, and uses a 28 nm design. It is made up of 1792 SPUs, 112 TAUs, and 32 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Geforce GTX 680		195 Watts
Radeon HD 7950 3GB		200 Watts
	Difference: 5 Watts (3%)

Memory Bandwidth

The Radeon HD 7950 3GB should in theory be much faster than the Geforce GTX 680 in general. (explain)

Radeon HD 7950 3GB		240000 MB/sec
Geforce GTX 680		192256 MB/sec
	Difference: 47744 (25%)

Texel Rate

The Geforce GTX 680 should be much (about 44%) faster with regards to anisotropic filtering than the Radeon HD 7950 3GB. (explain)

Geforce GTX 680		128768 Mtexels/sec
Radeon HD 7950 3GB		89600 Mtexels/sec
	Difference: 39168 (44%)

Pixel Rate

The Geforce GTX 680 is much (about 26%) better at AA than the Radeon HD 7950 3GB, and also should be capable of handling higher screen resolutions without slowing down too much. (explain)

Geforce GTX 680		32192 Mpixels/sec
Radeon HD 7950 3GB		25600 Mpixels/sec
	Difference: 6592 (26%)

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 maximum amount of information (in units of megabytes per second) that can be transferred over the external memory interface in a second. It is calculated by multiplying the card's interface width by its memory speed. In the case of DDR type RAM, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the better 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 texture map elements (texels) that can be applied in one second. This number is worked out by multiplying the total texture units by the core speed of the chip. The better this number, 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 amount of pixels the graphics card could possibly write to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.