Radeon HD 4850 X2 512MB vs Radeon R5 M255

Intro

Compare all 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 RAM works at a frequency of 1000 MHz on this specific card. It features 320 SPUs along with 20 Texture Address Units and 8 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Theoretically, the Radeon HD 4850 X2 512MB should be quite a bit faster than the Radeon R5 M255 overall. (explain)

Radeon HD 4850 X2 512MB		127104 MB/sec
Radeon R5 M255		16000 MB/sec
	Difference: 111104 (694%)

Texel Rate

The Radeon HD 4850 X2 512MB is a lot (approximately 166%) more effective at anisotropic filtering than the Radeon R5 M255. (explain)

Radeon HD 4850 X2 512MB		50000 Mtexels/sec
Radeon R5 M255		18800 Mtexels/sec
	Difference: 31200 (166%)

Pixel Rate

The Radeon HD 4850 X2 512MB is quite a bit (approximately 166%) more effective at FSAA than the Radeon R5 M255, and also will be capable of handling higher resolutions more effectively. (explain)

Radeon HD 4850 X2 512MB		20000 Mpixels/sec
Radeon R5 M255		7520 Mpixels/sec
	Difference: 12480 (166%)

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.

One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the max amount of information (counted in megabytes per second) that can be transported past the external memory interface in a second. The number is calculated by multiplying the card's bus width by the speed of its memory. In the case of DDR type memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed in one second. This number is worked out by multiplying the total texture units by the core speed of the chip. The higher this number, 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 number of pixels that the graphics chip could possibly record to its local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the number of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on lots of other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.