GeForce 8600 GT 1GB GDDR3 vs GeForce GT 420

Intro

Compare those specs to the GeForce GT 420, which features clock speeds of 700 MHz on the GPU, and 900 MHz on the 2048 MB of GDDR3 RAM. It features 48 SPUs along with 8 Texture Address Units and 4 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8600 GT 1GB GDDR3		47 Watts
GeForce GT 420		50 Watts
	Difference: 3 Watts (6%)

Memory Bandwidth

As far as performance goes, the GeForce GT 420 should in theory be much superior to the GeForce 8600 GT 1GB GDDR3 overall. (explain)

GeForce GT 420		28800 MB/sec
GeForce 8600 GT 1GB GDDR3		22400 MB/sec
	Difference: 6400 (29%)

Texel Rate

The GeForce 8600 GT 1GB GDDR3 is much (more or less 54%) better at anisotropic filtering than the GeForce GT 420. (explain)

GeForce 8600 GT 1GB GDDR3		8640 Mtexels/sec
GeForce GT 420		5600 Mtexels/sec
	Difference: 3040 (54%)

Pixel Rate

If running with high levels of AA is important to you, then the GeForce 8600 GT 1GB GDDR3 is superior to the GeForce GT 420, by a large margin. (explain)

GeForce 8600 GT 1GB GDDR3		4320 Mpixels/sec
GeForce GT 420		2800 Mpixels/sec
	Difference: 1520 (54%)

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 largest amount of information (measured in MB per second) that can be moved past the external memory interface within a second. The number is worked out by multiplying the card's interface width by the speed of its memory. In the case of DDR type RAM, it should be multiplied by 2 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 number of texture map elements (texels) that are processed per second. This figure is calculated by multiplying the total number of texture units 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 in a second.

Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly record to the local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.