Radeon HD 4770 vs Radeon HD 6950

Intro

Compare all that to the Radeon HD 6950, which features a core clock speed of 800 MHz and a GDDR5 memory speed of 1250 MHz. It also uses a 256-bit bus, and makes use of a 40 nm design. It is made up of 1408 SPUs, 88 Texture Address Units, and 32 Raster Operation Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4770		80 Watts
Radeon HD 6950		200 Watts
	Difference: 120 Watts (150%)

Memory Bandwidth

Performance-wise, the Radeon HD 6950 should in theory be much better than the Radeon HD 4770 overall. (explain)

Radeon HD 6950		160000 MB/sec
Radeon HD 4770		51200 MB/sec
	Difference: 108800 (213%)

Texel Rate

The Radeon HD 6950 should be a lot (more or less 193%) better at anisotropic filtering than the Radeon HD 4770. (explain)

Radeon HD 6950		70400 Mtexels/sec
Radeon HD 4770		24000 Mtexels/sec
	Difference: 46400 (193%)

Pixel Rate

If running with a high resolution is important to you, then the Radeon HD 6950 is superior to the Radeon HD 4770, by a large margin. (explain)

Radeon HD 6950		25600 Mpixels/sec
Radeon HD 4770		12000 Mpixels/sec
	Difference: 13600 (113%)

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 largest amount of information (counted in MB per second) that can be transported over the external memory interface within a second. It is calculated by multiplying the interface width by its memory speed. If it uses DDR RAM, it should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the bandwidth is, 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 can be processed 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 this number, the better the graphics 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 could possibly write to its local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.