GeForce 820M vs Radeon R9 M270X

Intro

Compare those specs to the Radeon R9 M270X, which makes use of a 28 nm design. AMD has clocked the core speed at 725 MHz. The GDDR5 memory is set to run at a speed of 1125 MHz on this particular card. It features 640 SPUs along with 40 TAUs and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

The Radeon R9 M270X, in theory, should be much faster than the GeForce 820M in general. (explain)

Radeon R9 M270X		72000 MB/sec
GeForce 820M		16000 MB/sec
	Difference: 56000 (350%)

Texel Rate

The Radeon R9 M270X is quite a bit (more or less 152%) better at texture filtering than the GeForce 820M. (explain)

Radeon R9 M270X		29000 Mtexels/sec
GeForce 820M		11504 Mtexels/sec
	Difference: 17496 (152%)

Pixel Rate

The Radeon R9 M270X is a lot (about 303%) better at anti-aliasing than the GeForce 820M, and also should be able to handle higher screen resolutions more effectively. (explain)

Radeon R9 M270X		11600 Mpixels/sec
GeForce 820M		2876 Mpixels/sec
	Difference: 8724 (303%)

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 maximum amount of data (measured in megabytes per second) that can be transported across the external memory interface in a second. It's worked out by multiplying the bus width by its memory clock speed. In the case of DDR memory, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the memory bandwidth, the better 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 amount of texture map elements (texels) that are processed per second. This figure is worked out by multiplying the total number of 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 handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip can possibly record to its local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of colour ROPs by the the card's clock speed. 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 rate also depends on quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.