GeForce GT 420 vs GeForce GTX 580

Intro

Compare those specs to the GeForce GTX 580, which has a clock frequency of 772 MHz and a GDDR5 memory speed of 1002 MHz. It also uses a 384-bit bus, and uses a 40 nm design. It features 512 SPUs, 64 TAUs, and 48 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 420		50 Watts
GeForce GTX 580		244 Watts
	Difference: 194 Watts (388%)

Memory Bandwidth

Theoretically speaking, the GeForce GTX 580 should be a lot faster than the GeForce GT 420 in general. (explain)

GeForce GTX 580		192384 MB/sec
GeForce GT 420		28800 MB/sec
	Difference: 163584 (568%)

Texel Rate

The GeForce GTX 580 will be a lot (approximately 782%) better at anisotropic filtering than the GeForce GT 420. (explain)

GeForce GTX 580		49408 Mtexels/sec
GeForce GT 420		5600 Mtexels/sec
	Difference: 43808 (782%)

Pixel Rate

If running with a high resolution is important to you, then the GeForce GTX 580 is the winner, by far. (explain)

GeForce GTX 580		37056 Mpixels/sec
GeForce GT 420		2800 Mpixels/sec
	Difference: 34256 (1223%)

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 maximum amount of information (measured in megabytes per second) that can be transferred over the external memory interface within a second. The number is calculated by multiplying the bus width by its memory speed. If it uses DDR type RAM, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied in one 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 video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.

Pixel Rate: Pixel rate is the most pixels the video card can possibly record to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of colour ROPs by the clock speed of the card. 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 rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.