GeForce 8400 GS 512MB vs Radeon HD 6870

Intro

Compare all that to the Radeon HD 6870, which has core clock speeds of 900 MHz on the GPU, and 1050 MHz on the 1024 MB of GDDR5 RAM. It features 1120 SPUs along with 56 TAUs and 32 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8400 GS 512MB		40 Watts
Radeon HD 6870		151 Watts
	Difference: 111 Watts (278%)

Memory Bandwidth

The Radeon HD 6870 should theoretically perform a lot faster than the GeForce 8400 GS 512MB in general. (explain)

Radeon HD 6870		134400 MB/sec
GeForce 8400 GS 512MB		6400 MB/sec
	Difference: 128000 (2000%)

Texel Rate

The Radeon HD 6870 is a lot (about 869%) better at AF than the GeForce 8400 GS 512MB. (explain)

Radeon HD 6870		50400 Mtexels/sec
GeForce 8400 GS 512MB		5200 Mtexels/sec
	Difference: 45200 (869%)

Pixel Rate

If running with high levels of AA is important to you, then the Radeon HD 6870 is superior to the GeForce 8400 GS 512MB, and very much so. (explain)

Radeon HD 6870		28800 Mpixels/sec
GeForce 8400 GS 512MB		2600 Mpixels/sec
	Difference: 26200 (1008%)

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 (measured in megabytes per second) that can be moved over the external memory interface in a second. It's worked out by multiplying the card's bus width by the speed of its memory. If it uses DDR type memory, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better 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 number 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 better 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 amount of pixels that the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.