GeForce 820M vs Radeon R9 M385X

Intro

Compare that to the Radeon R9 M385X, which features clock speeds of 1100 MHz on the GPU, and 1500 MHz on the 4096 MB of GDDR5 memory. It features 896 SPUs along with 56 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Theoretically speaking, the Radeon R9 M385X should be 500% quicker than the GeForce 820M in general, due to its greater bandwidth. (explain)

Radeon R9 M385X		96000 MB/sec
GeForce 820M		16000 MB/sec
	Difference: 80000 (500%)

Texel Rate

The Radeon R9 M385X is quite a bit (about 435%) better at AF than the GeForce 820M. (explain)

Radeon R9 M385X		61600 Mtexels/sec
GeForce 820M		11504 Mtexels/sec
	Difference: 50096 (435%)

Pixel Rate

The Radeon R9 M385X is a lot (more or less 512%) better at AA than the GeForce 820M, and should be able to handle higher resolutions without slowing down too much. (explain)

Radeon R9 M385X		17600 Mpixels/sec
GeForce 820M		2876 Mpixels/sec
	Difference: 14724 (512%)

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 maximum amount of information (measured in megabytes per second) that can be transported across the external memory interface within a second. It's calculated by multiplying the bus width by its memory clock speed. If it uses DDR type memory, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

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

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly record to its local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Raster Operations Pipelines by the the card's clock speed. 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 rate is also dependant on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.