GeForce GT 420 vs Radeon HD 5670

Intro

Compare that to the Radeon HD 5670, which has GPU clock speed of 775 MHz, and 1024 MB of GDDR5 memory running at 1000 MHz through a 128-bit bus. It also features 400(80x5) Stream Processors, 20 TAUs, and 8 Raster Operation Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 420		50 Watts
Radeon HD 5670		61 Watts
	Difference: 11 Watts (22%)

Memory Bandwidth

The Radeon HD 5670 should in theory perform much faster than the GeForce GT 420 overall. (explain)

Radeon HD 5670		64000 MB/sec
GeForce GT 420		28800 MB/sec
	Difference: 35200 (122%)

Texel Rate

The Radeon HD 5670 is a lot (about 177%) better at AF than the GeForce GT 420. (explain)

Radeon HD 5670		15500 Mtexels/sec
GeForce GT 420		5600 Mtexels/sec
	Difference: 9900 (177%)

Pixel Rate

The Radeon HD 5670 will be quite a bit (approximately 121%) faster with regards to FSAA than the GeForce GT 420, and also should be capable of handling higher screen resolutions more effectively. (explain)

Radeon HD 5670		6200 Mpixels/sec
GeForce GT 420		2800 Mpixels/sec
	Difference: 3400 (121%)

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 max amount of information (counted in megabytes per second) that can be transported across the external memory interface in a second. It's worked out by multiplying the interface width by its memory clock speed. If the card has 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 better 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 per second. This is calculated by multiplying the total amount of texture units of the card by the core speed of the chip. The better the texel rate, the better the video 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 number of pixels the video card could possibly write to its local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on quite a few other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.