GeForce 825M vs Radeon R9 390 8G

Intro

Compare that to the Radeon R9 390 8G, which features clock speeds of 1000 MHz on the GPU, and 1500 MHz on the 8192 MB of GDDR5 memory. It features 2560 SPUs along with 160 Texture Address Units and 64 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 825M		33 Watts
Radeon R9 390 8G		275 Watts
	Difference: 242 Watts (733%)

Memory Bandwidth

The Radeon R9 390 8G should in theory be much faster than the GeForce 825M overall. (explain)

Radeon R9 390 8G		384000 MB/sec
GeForce 825M		14400 MB/sec
	Difference: 369600 (2567%)

Texel Rate

The Radeon R9 390 8G is much (approximately 1076%) faster with regards to texture filtering than the GeForce 825M. (explain)

Radeon R9 390 8G		160000 Mtexels/sec
GeForce 825M		13600 Mtexels/sec
	Difference: 146400 (1076%)

Pixel Rate

If running with a high screen resolution is important to you, then the Radeon R9 390 8G is the winner, by far. (explain)

Radeon R9 390 8G		64000 Mpixels/sec
GeForce 825M		6800 Mpixels/sec
	Difference: 57200 (841%)

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 information (measured in MB per second) that can be transferred over the external memory interface in a second. It's calculated by multiplying the interface width by its memory clock speed. If it uses DDR RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

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

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly write to its local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on lots of other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.