Radeon HD 3870 512MB vs Radeon HD 6950

Intro

Compare those specifications to the Radeon HD 6950, which comes with GPU core speed of 800 MHz, and 1024 MB of GDDR5 memory set to run at 1250 MHz through a 256-bit bus. It also is comprised of 1408 SPUs, 88 Texture Address Units, and 32 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 3870 512MB		106 Watts
Radeon HD 6950		200 Watts
	Difference: 94 Watts (89%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 6950 should perform much faster than the Radeon HD 3870 512MB overall. (explain)

Radeon HD 6950		160000 MB/sec
Radeon HD 3870 512MB		57600 MB/sec
	Difference: 102400 (178%)

Texel Rate

The Radeon HD 6950 should be a lot (more or less 468%) faster with regards to AF than the Radeon HD 3870 512MB. (explain)

Radeon HD 6950		70400 Mtexels/sec
Radeon HD 3870 512MB		12400 Mtexels/sec
	Difference: 58000 (468%)

Pixel Rate

The Radeon HD 6950 is quite a bit (about 106%) better at AA than the Radeon HD 3870 512MB, and should be capable of handling higher screen resolutions while still performing well. (explain)

Radeon HD 6950		25600 Mpixels/sec
Radeon HD 3870 512MB		12400 Mpixels/sec
	Difference: 13200 (106%)

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 max amount of data (in units of megabytes per second) that can be transported over the external memory interface within a second. It's calculated by multiplying the card's bus width by its memory clock speed. If the card has DDR RAM, the result should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly write to the local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate is also dependant on many other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.