GeForce 8800 GTS (G80) 640MB vs GeForce GT 420

Intro

Compare all that to the GeForce GT 420, which comes with a GPU core clock speed of 700 MHz, and 2048 MB of GDDR3 RAM set to run at 900 MHz through a 128-bit bus. It also features 48 Stream Processors, 8 Texture Address Units, and 4 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 420		50 Watts
GeForce 8800 GTS (G80) 640MB		143 Watts
	Difference: 93 Watts (186%)

Memory Bandwidth

Performance-wise, the GeForce 8800 GTS (G80) 640MB should in theory be quite a bit superior to the GeForce GT 420 in general. (explain)

GeForce 8800 GTS (G80) 640MB		63360 MB/sec
GeForce GT 420		28800 MB/sec
	Difference: 34560 (120%)

Texel Rate

The GeForce 8800 GTS (G80) 640MB is much (approximately 340%) faster with regards to texture filtering than the GeForce GT 420. (explain)

GeForce 8800 GTS (G80) 640MB		24624 Mtexels/sec
GeForce GT 420		5600 Mtexels/sec
	Difference: 19024 (340%)

Pixel Rate

If using a high screen resolution is important to you, then the GeForce 8800 GTS (G80) 640MB is superior to the GeForce GT 420, and very much so. (explain)

GeForce 8800 GTS (G80) 640MB		10260 Mpixels/sec
GeForce GT 420		2800 Mpixels/sec
	Difference: 7460 (266%)

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 max amount of information (in units of MB per second) that can be moved over the external memory interface within a second. It is calculated by multiplying the card's interface width by the speed of its memory. If the card has DDR memory, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed per second. This number is calculated by multiplying the total number of texture units by the core clock speed of the chip. The better 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 most pixels that the graphics card could possibly record to its local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Raster Operations Pipelines by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.