GeForce 8400 GS 512MB vs Radeon R5 M255

Intro

Compare all of that to the Radeon R5 M255, which makes use of a 28 nm design. AMD has set the core speed at 940 MHz. The DDR3 memory runs at a speed of 1000 MHz on this specific model. It features 320 SPUs along with 20 Texture Address Units and 8 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

In theory, the Radeon R5 M255 should be much faster than the GeForce 8400 GS 512MB in general. (explain)

Radeon R5 M255		16000 MB/sec
GeForce 8400 GS 512MB		6400 MB/sec
	Difference: 9600 (150%)

Texel Rate

The Radeon R5 M255 will be much (more or less 262%) better at texture filtering than the GeForce 8400 GS 512MB. (explain)

Radeon R5 M255		18800 Mtexels/sec
GeForce 8400 GS 512MB		5200 Mtexels/sec
	Difference: 13600 (262%)

Pixel Rate

If running with a high screen resolution is important to you, then the Radeon R5 M255 is the winner, and very much so. (explain)

Radeon R5 M255		7520 Mpixels/sec
GeForce 8400 GS 512MB		2600 Mpixels/sec
	Difference: 4920 (189%)

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 MB per second) that can be transferred over the external memory interface within a second. It is worked out by multiplying the card's bus width by its memory speed. If it uses DDR type RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster 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 applied in one second. This number is worked out by multiplying the total amount of texture units by the core speed of the chip. The higher this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly record to its local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on quite a few other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.