GeForce GTX 850M vs Radeon HD 3870 X2 1GB

Intro

Compare all of that to the Radeon HD 3870 X2 1GB, which features clock speeds of 825 MHz on the GPU, and 1126 MHz on the 1024 MB of GDDR4 RAM. It features 320(64x5) SPUs along with 16 Texture Address Units and 16 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Memory Bandwidth

The Radeon HD 3870 X2 1GB, in theory, should perform a lot faster than the GeForce GTX 850M overall. (explain)

Radeon HD 3870 X2 1GB		144128 MB/sec
GeForce GTX 850M		32000 MB/sec
	Difference: 112128 (350%)

Texel Rate

The GeForce GTX 850M should be much (about 33%) better at anisotropic filtering than the Radeon HD 3870 X2 1GB. (explain)

GeForce GTX 850M		35040 Mtexels/sec
Radeon HD 3870 X2 1GB		26400 Mtexels/sec
	Difference: 8640 (33%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 3870 X2 1GB is the winner, and very much so. (explain)

Radeon HD 3870 X2 1GB		26400 Mpixels/sec
GeForce GTX 850M		14016 Mpixels/sec
	Difference: 12384 (88%)

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: Bandwidth is the maximum amount of information (counted in megabytes per second) that can be transported over the external memory interface in a second. It's worked out by multiplying the card's bus width by its memory clock speed. In the case of DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the most pixels the video card can possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the max fill rate.