Radeon HD 6850 vs Radeon HD 6870

Intro

Compare those specs to the Radeon HD 6870, which features core clock speeds of 900 MHz on the GPU, and 1050 MHz on the 1024 MB of GDDR5 memory. It features 1120 SPUs along with 56 TAUs and 32 ROPs.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 6850		127 Watts
Radeon HD 6870		151 Watts
	Difference: 24 Watts (19%)

Memory Bandwidth

In theory, the Radeon HD 6870 is 5% faster than the Radeon HD 6850 overall, because of its higher bandwidth. (explain)

Radeon HD 6870		134400 MB/sec
Radeon HD 6850		128000 MB/sec
	Difference: 6400 (5%)

Texel Rate

The Radeon HD 6870 will be a lot (approximately 35%) better at anisotropic filtering than the Radeon HD 6850. (explain)

Radeon HD 6870		50400 Mtexels/sec
Radeon HD 6850		37200 Mtexels/sec
	Difference: 13200 (35%)

Pixel Rate

If running with a high screen resolution is important to you, then the Radeon HD 6870 is a better choice, but not by far. (explain)

Radeon HD 6870		28800 Mpixels/sec
Radeon HD 6850		24800 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 data (measured in MB per second) that can be transported past the external memory interface in a second. It is worked out by multiplying the bus width by the speed of its memory. In the case of DDR type RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied in one second. This is calculated by multiplying the total number of texture units of the card by the core 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 applied per second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly write to the local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the number of Raster Operations Pipelines by the the core 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 quite a few other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.