GeForce GTX 870M vs Radeon HD 3870 512MB

Intro

Compare all that to the Radeon HD 3870 512MB, which makes use of a 55 nm design. AMD has clocked the core frequency at 775 MHz. The GDDR3 memory runs at a speed of 900 MHz on this card. It features 320(64x5) SPUs along with 16 TAUs and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 3870 512MB		106 Watts
GeForce GTX 870M		110 Watts
	Difference: 4 Watts (4%)

Memory Bandwidth

Performance-wise, the GeForce GTX 870M should theoretically be much better than the Radeon HD 3870 512MB in general. (explain)

GeForce GTX 870M		96000 MB/sec
Radeon HD 3870 512MB		57600 MB/sec
	Difference: 38400 (67%)

Texel Rate

The GeForce GTX 870M should be much (more or less 750%) more effective at anisotropic filtering than the Radeon HD 3870 512MB. (explain)

GeForce GTX 870M		105392 Mtexels/sec
Radeon HD 3870 512MB		12400 Mtexels/sec
	Difference: 92992 (750%)

Pixel Rate

If running with high levels of AA is important to you, then the GeForce GTX 870M is the winner, and very much so. (explain)

GeForce GTX 870M		22584 Mpixels/sec
Radeon HD 3870 512MB		12400 Mpixels/sec
	Difference: 10184 (82%)

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: Bandwidth is the largest amount of information (in units of MB per second) that can be transferred past the external memory interface in one second. It's calculated by multiplying the card's bus width by its memory clock speed. If it uses DDR memory, it must be multiplied by 2 again. If 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 higher screen resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed in one second. This number is calculated by multiplying the total texture units of the card 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 in a second.

Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly record to its local memory per second - measured in millions of pixels per second. The figure is worked out 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 rate is also dependant 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.