GeForce 8800 GT 256MB vs Radeon HD 6870

Intro

Compare all of that to the Radeon HD 6870, which has a core clock frequency of 900 MHz and a GDDR5 memory frequency of 1050 MHz. It also uses a 256-bit bus, and makes use of a 40 nm design. It is made up of 1120 SPUs, 56 Texture Address Units, and 32 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8800 GT 256MB		105 Watts
Radeon HD 6870		151 Watts
	Difference: 46 Watts (44%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 6870 should be a lot faster than the GeForce 8800 GT 256MB in general. (explain)

Radeon HD 6870		134400 MB/sec
GeForce 8800 GT 256MB		44800 MB/sec
	Difference: 89600 (200%)

Texel Rate

The Radeon HD 6870 should be a lot (about 50%) more effective at AF than the GeForce 8800 GT 256MB. (explain)

Radeon HD 6870		50400 Mtexels/sec
GeForce 8800 GT 256MB		33600 Mtexels/sec
	Difference: 16800 (50%)

Pixel Rate

The Radeon HD 6870 will be quite a bit (about 200%) faster with regards to AA than the GeForce 8800 GT 256MB, and also should be capable of handling higher screen resolutions without losing too much performance. (explain)

Radeon HD 6870		28800 Mpixels/sec
GeForce 8800 GT 256MB		9600 Mpixels/sec
	Difference: 19200 (200%)

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 data (measured in megabytes per second) that can be transported over the external memory interface in a second. It is calculated by multiplying the card's interface width by its memory clock speed. If the card has DDR type RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better 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 can be processed in one second. This is worked out by multiplying the total number of texture units of the card by the core clock speed of the chip. The higher the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.

Pixel Rate: Pixel rate is the most pixels the video card can possibly write to the local memory in one 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 - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate is also dependant on quite a few other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the max fill rate.