Radeon HD 6790 vs Radeon HD 6850

Intro

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

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 6850		127 Watts
Radeon HD 6790		150 Watts
	Difference: 23 Watts (18%)

Memory Bandwidth

The Radeon HD 6790 should theoretically be a bit faster than the Radeon HD 6850 in general. (explain)

Radeon HD 6790		134400 MB/sec
Radeon HD 6850		128000 MB/sec
	Difference: 6400 (5%)

Texel Rate

The Radeon HD 6850 should be a small bit (more or less 11%) faster with regards to AF than the Radeon HD 6790. (explain)

Radeon HD 6850		37200 Mtexels/sec
Radeon HD 6790		33600 Mtexels/sec
	Difference: 3600 (11%)

Pixel Rate

The Radeon HD 6850 will be a lot (more or less 85%) more effective at FSAA than the Radeon HD 6790, and will be capable of handling higher screen resolutions without slowing down too much. (explain)

Radeon HD 6850		24800 Mpixels/sec
Radeon HD 6790		13440 Mpixels/sec
	Difference: 11360 (85%)

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 maximum amount of information (counted in MB per second) that can be transferred past the external memory interface within a second. The number is worked out by multiplying the interface width by its memory clock speed. In the case of DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher 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 are processed per second. This 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 applied in a second.

Pixel Rate: Pixel rate is the most pixels the graphics card could possibly write to the local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the amount of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as 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 of the card - the lower the bandwidth is, the lower the ability to reach the max fill rate.