GeForce GT 420 vs Radeon HD 4670 512MB

Intro

Compare those specifications to the Radeon HD 4670 512MB, which has GPU clock speed of 750 MHz, and 512 MB of GDDR4/GDDR3/DDR3/DDR2 RAM set to run at 1000 MHz through a 128-bit bus. It also is made up of 320(64x5) SPUs, 32 Texture Address Units, 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 4670 512MB		70 Watts
	Difference: 20 Watts (40%)

Memory Bandwidth

The Radeon HD 4670 512MB, in theory, should perform a small bit faster than the GeForce GT 420 overall. (explain)

Radeon HD 4670 512MB		32000 MB/sec
GeForce GT 420		28800 MB/sec
	Difference: 3200 (11%)

Texel Rate

The Radeon HD 4670 512MB should be a lot (approximately 329%) better at AF than the GeForce GT 420. (explain)

Radeon HD 4670 512MB		24000 Mtexels/sec
GeForce GT 420		5600 Mtexels/sec
	Difference: 18400 (329%)

Pixel Rate

The Radeon HD 4670 512MB is quite a bit (about 114%) more effective at anti-aliasing than the GeForce GT 420, and also should be able to handle higher screen resolutions without slowing down too much. (explain)

Radeon HD 4670 512MB		6000 Mpixels/sec
GeForce GT 420		2800 Mpixels/sec
	Difference: 3200 (114%)

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 largest amount of data (counted in MB per second) that can be transferred over the external memory interface in a second. The number is calculated by multiplying the card's interface width by the speed of its memory. In the case of DDR RAM, it must 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, High Dynamic Range and higher screen resolutions.

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

Pixel Rate: Pixel rate is the most pixels that the graphics chip can possibly write to its local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the number of colour ROPs 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 fill rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.