GeForce 8400 GS 512MB vs GeForce 8800 GTX

Intro

Compare those specs to the GeForce 8800 GTX, which features GPU clock speed of 575 MHz, and 768 MB of GDDR3 RAM running at 900 MHz through a 384-bit bus. It also is made up of 128 Stream Processors, 64 TAUs, and 24 Raster Operation Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8400 GS 512MB		40 Watts
GeForce 8800 GTX		155 Watts
	Difference: 115 Watts (288%)

Memory Bandwidth

The GeForce 8800 GTX should theoretically be quite a bit faster than the GeForce 8400 GS 512MB overall. (explain)

GeForce 8800 GTX		86400 MB/sec
GeForce 8400 GS 512MB		6400 MB/sec
	Difference: 80000 (1250%)

Texel Rate

The GeForce 8800 GTX is a lot (more or less 608%) more effective at anisotropic filtering than the GeForce 8400 GS 512MB. (explain)

GeForce 8800 GTX		36800 Mtexels/sec
GeForce 8400 GS 512MB		5200 Mtexels/sec
	Difference: 31600 (608%)

Pixel Rate

If running with a high screen resolution is important to you, then the GeForce 8800 GTX is the winner, by far. (explain)

GeForce 8800 GTX		13800 Mpixels/sec
GeForce 8400 GS 512MB		2600 Mpixels/sec
	Difference: 11200 (431%)

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: Bandwidth is the largest amount of information (counted in megabytes per second) that can be moved across the external memory interface in one second. It is calculated by multiplying the card's bus width by its memory speed. If the card has DDR type memory, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be 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 video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.

Pixel Rate: Pixel rate is the maximum number of pixels the video card can possibly write to its local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the number of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate also depends on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.