GeForce 8400 GS 512MB vs GeForce 8500 GT

Intro

Compare those specs to the GeForce 8500 GT, which features a GPU core clock speed of 450 MHz, and 512 MB of DDR2 memory running at 400 MHz through a 128-bit bus. It also features 16 SPUs, 8 Texture Address Units, and 4 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8400 GS 512MB		40 Watts
GeForce 8500 GT		45 Watts
	Difference: 5 Watts (13%)

Memory Bandwidth

In theory, the GeForce 8500 GT should be 100% quicker than the GeForce 8400 GS 512MB overall, because of its greater data rate. (explain)

GeForce 8500 GT		12800 MB/sec
GeForce 8400 GS 512MB		6400 MB/sec
	Difference: 6400 (100%)

Texel Rate

The GeForce 8400 GS 512MB should be a lot (about 44%) more effective at texture filtering than the GeForce 8500 GT. (explain)

GeForce 8400 GS 512MB		5200 Mtexels/sec
GeForce 8500 GT		3600 Mtexels/sec
	Difference: 1600 (44%)

Pixel Rate

If using high levels of AA is important to you, then the GeForce 8400 GS 512MB is a better choice, by far. (explain)

GeForce 8400 GS 512MB		2600 Mpixels/sec
GeForce 8500 GT		1800 Mpixels/sec
	Difference: 800 (44%)

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 data (measured in megabytes per second) that can be transferred past the external memory interface within a second. It is calculated by multiplying the card's bus width by its memory clock speed. In the case of DDR type memory, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied in one second. This number is worked out by multiplying the total texture units of the card by the core speed of the chip. The better the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.

Pixel Rate: Pixel rate is the most pixels the graphics card could possibly write to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of Raster Operations Pipelines by the the card's 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 also depends on quite a few other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.