GeForce GT 420 vs Radeon HD 6950

Intro

Compare those specifications to the Radeon HD 6950, which comes with a clock speed of 800 MHz and a GDDR5 memory speed of 1250 MHz. It also uses a 256-bit bus, and uses a 40 nm design. It is made up of 1408 SPUs, 88 Texture Address Units, and 32 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 420		50 Watts
Radeon HD 6950		200 Watts
	Difference: 150 Watts (300%)

Memory Bandwidth

As far as performance goes, the Radeon HD 6950 should in theory be quite a bit better than the GeForce GT 420 overall. (explain)

Radeon HD 6950		160000 MB/sec
GeForce GT 420		28800 MB/sec
	Difference: 131200 (456%)

Texel Rate

The Radeon HD 6950 will be much (about 1157%) more effective at anisotropic filtering than the GeForce GT 420. (explain)

Radeon HD 6950		70400 Mtexels/sec
GeForce GT 420		5600 Mtexels/sec
	Difference: 64800 (1157%)

Pixel Rate

If running with a high resolution is important to you, then the Radeon HD 6950 is superior to the GeForce GT 420, and very much so. (explain)

Radeon HD 6950		25600 Mpixels/sec
GeForce GT 420		2800 Mpixels/sec
	Difference: 22800 (814%)

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 data (in units of MB per second) that can be transported over the external memory interface in a second. The number is worked out by multiplying the bus width by its memory speed. If the card has DDR type memory, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, 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 are applied per second. This is calculated by multiplying the total number of texture units by the core clock speed of the chip. The better this number, the better the 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 that the graphics chip could possibly write to the local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.