GeForce 8600 GT 512MB DDR2 vs GeForce GT 420

Intro

Compare those specifications to the GeForce GT 420, which uses a 40 nm design. nVidia has clocked the core frequency at 700 MHz. The GDDR3 memory runs at a frequency of 900 MHz on this card. It features 48 SPUs along with 8 TAUs and 4 Rasterization Operator Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8600 GT 512MB DDR2		47 Watts
GeForce GT 420		50 Watts
	Difference: 3 Watts (6%)

Memory Bandwidth

Theoretically speaking, the GeForce GT 420 should perform a lot faster than the GeForce 8600 GT 512MB DDR2 in general. (explain)

GeForce GT 420		28800 MB/sec
GeForce 8600 GT 512MB DDR2		12800 MB/sec
	Difference: 16000 (125%)

Texel Rate

The GeForce 8600 GT 512MB DDR2 is much (more or less 54%) more effective at texture filtering than the GeForce GT 420. (explain)

GeForce 8600 GT 512MB DDR2		8640 Mtexels/sec
GeForce GT 420		5600 Mtexels/sec
	Difference: 3040 (54%)

Pixel Rate

If using high levels of AA is important to you, then the GeForce 8600 GT 512MB DDR2 is the winner, and very much so. (explain)

GeForce 8600 GT 512MB DDR2		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: Bandwidth is the maximum amount of information (measured in megabytes per second) that can be transferred past the external memory interface in one second. The number is calculated by multiplying the bus width by its memory speed. If the card has DDR type memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the bandwidth is, 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 are processed per second. This number is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The better this number, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.

Pixel Rate: Pixel rate is the most pixels the graphics card can possibly write to its local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate is also dependant on lots of other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.