GeForce 820M vs Radeon HD 7950 3GB

Intro

Compare all of that to the Radeon HD 7950 3GB, which comes with a clock speed of 800 MHz and a GDDR5 memory speed of 1250 MHz. It also features a 384-bit bus, and makes use of a 28 nm design. It features 1792 SPUs, 112 Texture Address Units, and 32 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 820M		15 Watts
Radeon HD 7950 3GB		200 Watts
	Difference: 185 Watts (1233%)

Memory Bandwidth

The Radeon HD 7950 3GB should theoretically be a lot faster than the GeForce 820M in general. (explain)

Radeon HD 7950 3GB		240000 MB/sec
GeForce 820M		16000 MB/sec
	Difference: 224000 (1400%)

Texel Rate

The Radeon HD 7950 3GB will be much (more or less 679%) better at texture filtering than the GeForce 820M. (explain)

Radeon HD 7950 3GB		89600 Mtexels/sec
GeForce 820M		11504 Mtexels/sec
	Difference: 78096 (679%)

Pixel Rate

If running with a high resolution is important to you, then the Radeon HD 7950 3GB is a better choice, by a large margin. (explain)

Radeon HD 7950 3GB		25600 Mpixels/sec
GeForce 820M		2876 Mpixels/sec
	Difference: 22724 (790%)

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 (in units of MB per second) that can be moved over the external memory interface in a second. The number is calculated by multiplying the interface width by its memory clock speed. If it uses DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and higher screen 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 clock speed of the chip. The better the texel rate, the better the 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 maximum number of pixels that the graphics card could possibly write to its local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the number of colour ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate also depends on lots of other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.