Radeon HD 7950 3GB vs Radeon HD 7970

Intro

Compare those specifications to the Radeon HD 7970, which has core clock speeds of 925 MHz on the GPU, and 1375 MHz on the 3072 MB of GDDR5 memory. It features 2048 SPUs along with 128 Texture Address Units and 32 ROPs.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7950 3GB		200 Watts
Radeon HD 7970		250 Watts
	Difference: 50 Watts (25%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 7970 should be 10% quicker than the Radeon HD 7950 3GB overall, because of its higher data rate. (explain)

Radeon HD 7970		264000 MB/sec
Radeon HD 7950 3GB		240000 MB/sec
	Difference: 24000 (10%)

Texel Rate

The Radeon HD 7970 is quite a bit (about 32%) better at texture filtering than the Radeon HD 7950 3GB. (explain)

Radeon HD 7970		118400 Mtexels/sec
Radeon HD 7950 3GB		89600 Mtexels/sec
	Difference: 28800 (32%)

Pixel Rate

The Radeon HD 7970 will be a small bit (more or less 16%) faster with regards to full screen anti-aliasing than the Radeon HD 7950 3GB, and also will be capable of handling higher screen resolutions while still performing well. (explain)

Radeon HD 7970		29600 Mpixels/sec
Radeon HD 7950 3GB		25600 Mpixels/sec
	Difference: 4000 (16%)

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 MB per second) that can be transported past the external memory interface in one second. It is worked out by multiplying the interface width by the speed of its memory. If it uses DDR type RAM, it should be multiplied by 2 once again. If it uses 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 high resolutions.

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

Pixel Rate: Pixel rate is the most pixels the video card can possibly record to its local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Raster Operations Pipelines 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 output rate also depends on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.