GeForce 8600 GTS vs GeForce GTX 850M

Intro

Compare all that to the GeForce GTX 850M, which features a clock speed of 876 MHz and a DDR3 memory speed of 1000 MHz. It also uses a 128-bit bus, and uses a 28 nm design. It is made up of 640 SPUs, 40 Texture Address Units, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 850M		40 Watts
GeForce 8600 GTS		75 Watts
	Difference: 35 Watts (88%)

Memory Bandwidth

Both cards have exactly the same memory bandwidth, so theoretically they should perform exactly the same. (explain)

Texel Rate

The GeForce GTX 850M is much (more or less 224%) more effective at AF than the GeForce 8600 GTS. (explain)

GeForce GTX 850M		35040 Mtexels/sec
GeForce 8600 GTS		10800 Mtexels/sec
	Difference: 24240 (224%)

Pixel Rate

The GeForce GTX 850M is a lot (approximately 160%) better at full screen anti-aliasing than the GeForce 8600 GTS, and also able to handle higher screen resolutions more effectively. (explain)

GeForce GTX 850M		14016 Mpixels/sec
GeForce 8600 GTS		5400 Mpixels/sec
	Difference: 8616 (160%)

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 transported past the external memory interface in one second. It's calculated by multiplying the card's bus width by the speed of its memory. If the card has DDR type memory, the result should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher 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 texture map elements (texels) that are applied in one second. This figure is worked out by multiplying the total texture units by the core speed of the chip. The better this number, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.

Pixel Rate: Pixel rate is the most pixels that the graphics card could possibly write to its local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the amount of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on quite a few other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.