GeForce GT 420 vs GeForce GTX 275

Intro

Compare all that to the GeForce GTX 275, which comes with core speeds of 633 MHz on the GPU, and 1134 MHz on the 896 MB of GDDR3 RAM. It features 240 SPUs as well as 80 Texture Address Units and 28 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 420		50 Watts
GeForce GTX 275		219 Watts
	Difference: 169 Watts (338%)

Memory Bandwidth

Performance-wise, the GeForce GTX 275 should theoretically be quite a bit better than the GeForce GT 420 overall. (explain)

GeForce GTX 275		127008 MB/sec
GeForce GT 420		28800 MB/sec
	Difference: 98208 (341%)

Texel Rate

The GeForce GTX 275 should be much (about 804%) more effective at anisotropic filtering than the GeForce GT 420. (explain)

GeForce GTX 275		50640 Mtexels/sec
GeForce GT 420		5600 Mtexels/sec
	Difference: 45040 (804%)

Pixel Rate

If using a high resolution is important to you, then the GeForce GTX 275 is the winner, by far. (explain)

GeForce GTX 275		17724 Mpixels/sec
GeForce GT 420		2800 Mpixels/sec
	Difference: 14924 (533%)

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 megabytes per second) that can be moved across the external memory interface in a second. It is calculated by multiplying the card's bus 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 texture map elements (texels) that can be processed in one second. This is calculated by multiplying the total texture units of the card by the core clock speed of the chip. The higher the texel rate, the better the 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 maximum amount of pixels that the graphics card could possibly record to its local memory per 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 - sometimes also referred to as 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, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.