GeForce GT 420 vs GeForce GTX 480

Intro

Compare those specs to the GeForce GTX 480, which uses a 40 nm design. nVidia has clocked the core speed at 700 MHz. The GDDR5 memory is set to run at a speed of 924 MHz on this model. It features 480 SPUs along with 60 Texture Address Units and 48 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 420		50 Watts
GeForce GTX 480		250 Watts
	Difference: 200 Watts (400%)

Memory Bandwidth

In theory, the GeForce GTX 480 is 516% quicker than the GeForce GT 420 overall, due to its higher bandwidth. (explain)

GeForce GTX 480		177408 MB/sec
GeForce GT 420		28800 MB/sec
	Difference: 148608 (516%)

Texel Rate

The GeForce GTX 480 should be a lot (about 650%) faster with regards to AF than the GeForce GT 420. (explain)

GeForce GTX 480		42000 Mtexels/sec
GeForce GT 420		5600 Mtexels/sec
	Difference: 36400 (650%)

Pixel Rate

The GeForce GTX 480 will be much (more or less 1100%) more effective at AA than the GeForce GT 420, and also capable of handling higher resolutions without losing too much performance. (explain)

GeForce GTX 480		33600 Mpixels/sec
GeForce GT 420		2800 Mpixels/sec
	Difference: 30800 (1100%)

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 (measured in megabytes per second) that can be moved past the external memory interface in a second. It's calculated by multiplying the card's interface width by its memory speed. In the case of DDR type RAM, the result should be multiplied by 2 once 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 anti-aliasing, HDR and high resolutions.

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

Pixel Rate: Pixel rate is the maximum number of pixels the video card can possibly record to its local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the max fill rate.