GeForce GTX 285 2GB vs GeForce GTX 870M

Intro

Compare all that to the GeForce GTX 870M, which comes with a clock frequency of 941 MHz and a GDDR5 memory frequency of 1000 MHz. It also makes use of a 192-bit memory bus, and uses a 28 nm design. It is comprised of 1344 SPUs, 112 Texture Address Units, and 24 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 870M		110 Watts
GeForce GTX 285 2GB		204 Watts
	Difference: 94 Watts (85%)

Memory Bandwidth

Theoretically speaking, the GeForce GTX 285 2GB should be a lot faster than the GeForce GTX 870M in general. (explain)

GeForce GTX 285 2GB		158976 MB/sec
GeForce GTX 870M		96000 MB/sec
	Difference: 62976 (66%)

Texel Rate

The GeForce GTX 870M is quite a bit (approximately 103%) faster with regards to texture filtering than the GeForce GTX 285 2GB. (explain)

GeForce GTX 870M		105392 Mtexels/sec
GeForce GTX 285 2GB		51840 Mtexels/sec
	Difference: 53552 (103%)

Pixel Rate

If running with high levels of AA is important to you, then the GeForce GTX 870M is the winner, but only just. (explain)

GeForce GTX 870M		22584 Mpixels/sec
GeForce GTX 285 2GB		20736 Mpixels/sec
	Difference: 1848 (9%)

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 (counted in megabytes per second) that can be transported across the external memory interface within a second. The number is worked out by multiplying the card's bus width by its memory speed. If it uses DDR RAM, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied in one second. This is worked out by multiplying the total number of texture units by the core speed of the chip. The better this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels the video card can possibly write to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the number of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.