GeForce 940M vs Radeon HD 3870 X2 512MB

Intro

Compare those specs to the Radeon HD 3870 X2 512MB, which uses a 55 nm design. AMD has clocked the core frequency at 825 MHz. The GDDR3 memory is set to run at a speed of 900 MHz on this particular card. It features 320(64x5) SPUs as well as 16 Texture Address Units and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

The Radeon HD 3870 X2 512MB should in theory be quite a bit faster than the GeForce 940M overall. (explain)

Radeon HD 3870 X2 512MB		115200 MB/sec
GeForce 940M		16000 MB/sec
	Difference: 99200 (620%)

Texel Rate

The Radeon HD 3870 X2 512MB is a little bit (more or less 3%) faster with regards to texture filtering than the GeForce 940M. (explain)

Radeon HD 3870 X2 512MB		26400 Mtexels/sec
GeForce 940M		25728 Mtexels/sec
	Difference: 672 (3%)

Pixel Rate

The Radeon HD 3870 X2 512MB should be quite a bit (more or less 208%) better at FSAA than the GeForce 940M, and will be able to handle higher screen resolutions without slowing down too much. (explain)

Radeon HD 3870 X2 512MB		26400 Mpixels/sec
GeForce 940M		8576 Mpixels/sec
	Difference: 17824 (208%)

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 max amount of data (in units of megabytes per second) that can be transferred over the external memory interface within a second. It is calculated by multiplying the card's interface width by the speed of its memory. In the case of DDR RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the 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 processed in one second. This figure is calculated by multiplying the total texture units by the core speed of the chip. The higher the texel rate, the better the video card will be at 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 the video card could possibly write to the local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate also depends on quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.