Radeon HD 4790 vs Radeon HD 6950

Intro

Compare all that to the Radeon HD 6950, which comes with clock speeds of 800 MHz on the GPU, and 1250 MHz on the 1024 MB of GDDR5 RAM. It features 1408 SPUs along with 88 TAUs and 32 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Performance-wise, the Radeon HD 6950 should theoretically be much better than the Radeon HD 4790 overall. (explain)

Radeon HD 6950		160000 MB/sec
Radeon HD 4790		102400 MB/sec
	Difference: 57600 (56%)

Texel Rate

The Radeon HD 6950 is quite a bit (about 267%) more effective at texture filtering than the Radeon HD 4790. (explain)

Radeon HD 6950		70400 Mtexels/sec
Radeon HD 4790		19200 Mtexels/sec
	Difference: 51200 (267%)

Pixel Rate

The Radeon HD 6950 will be quite a bit (approximately 167%) better at anti-aliasing than the Radeon HD 4790, and also will be capable of handling higher resolutions better. (explain)

Radeon HD 6950		25600 Mpixels/sec
Radeon HD 4790		9600 Mpixels/sec
	Difference: 16000 (167%)

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 (counted in megabytes per second) that can be moved across the external memory interface in one second. It's worked out by multiplying the card's bus width by its memory speed. If the card has DDR type memory, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied in one second. This is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The better this number, 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 amount of pixels the graphics card could possibly record to its local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the number of Raster Operations Pipelines by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.