Radeon HD 3870 X2 1GB vs Radeon HD 6950 2GB

Intro

Compare all that to the Radeon HD 6950 2GB, which comes with clock speeds of 800 MHz on the GPU, and 1250 MHz on the 2048 MB of GDDR5 RAM. It features 1408 SPUs along with 88 TAUs and 32 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Theoretically, the Radeon HD 6950 2GB should perform a small bit faster than the Radeon HD 3870 X2 1GB overall. (explain)

Radeon HD 6950 2GB		160000 MB/sec
Radeon HD 3870 X2 1GB		144128 MB/sec
	Difference: 15872 (11%)

Texel Rate

The Radeon HD 6950 2GB will be a lot (about 167%) more effective at AF than the Radeon HD 3870 X2 1GB. (explain)

Radeon HD 6950 2GB		70400 Mtexels/sec
Radeon HD 3870 X2 1GB		26400 Mtexels/sec
	Difference: 44000 (167%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 3870 X2 1GB is the winner, but only just. (explain)

Radeon HD 3870 X2 1GB		26400 Mpixels/sec
Radeon HD 6950 2GB		25600 Mpixels/sec
	Difference: 800 (3%)

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.

One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the max amount of data (in units of MB per second) that can be transferred across the external memory interface within a second. It is worked out by multiplying the interface width by the speed of its memory. In the case of DDR memory, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher 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 number of texture map elements (texels) that are applied per second. This figure is worked out by multiplying the total amount of texture units by the core clock speed of the chip. The higher the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels the video card can possibly write to its local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number 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 rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.