Radeon HD 5850 vs Radeon HD 6850

Intro

Compare all that to the Radeon HD 6850, which has a clock frequency of 775 MHz and a GDDR5 memory frequency of 1000 MHz. It also makes use of a 256-bit bus, and uses a 40 nm design. It features 960 SPUs, 48 Texture Address Units, and 32 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 6850		127 Watts
Radeon HD 5850		151 Watts
	Difference: 24 Watts (19%)

Memory Bandwidth

Both cards have the exact same bandwidth, so theoretically they should have the same performance. (explain)

Texel Rate

The Radeon HD 5850 will be much (about 40%) more effective at anisotropic filtering than the Radeon HD 6850. (explain)

Radeon HD 5850		52200 Mtexels/sec
Radeon HD 6850		37200 Mtexels/sec
	Difference: 15000 (40%)

Pixel Rate

The Radeon HD 6850 should be a little bit (about 7%) more effective at full screen anti-aliasing than the Radeon HD 5850, and will be capable of handling higher screen resolutions more effectively. (explain)

Radeon HD 6850		24800 Mpixels/sec
Radeon HD 5850		23200 Mpixels/sec
	Difference: 1600 (7%)

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 (in units of MB per second) that can be transferred past the external memory interface within a second. The number is worked out by multiplying the card's interface width by the speed of its memory. In the case of DDR type memory, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the faster 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 amount of texture map elements (texels) that are applied in one second. This is calculated by multiplying the total amount of texture units of the card by the core speed of the chip. The higher this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card could possibly write to its local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the number of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on lots of other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.