GeForce 840M vs GeForce 8600 GT 1GB GDDR3

Intro

Compare all of that to the GeForce 8600 GT 1GB GDDR3, which features clock speeds of 540 MHz on the GPU, and 700 MHz on the 1024 MB of GDDR3 memory. It features 32 SPUs along with 16 Texture Address Units and 8 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 840M		30 Watts
GeForce 8600 GT 1GB GDDR3		47 Watts
	Difference: 17 Watts (57%)

Memory Bandwidth

The GeForce 8600 GT 1GB GDDR3, in theory, should perform quite a bit faster than the GeForce 840M in general. (explain)

GeForce 8600 GT 1GB GDDR3		22400 MB/sec
GeForce 840M		16000 MB/sec
	Difference: 6400 (40%)

Texel Rate

The GeForce 840M is much (more or less 186%) more effective at AF than the GeForce 8600 GT 1GB GDDR3. (explain)

GeForce 840M		24696 Mtexels/sec
GeForce 8600 GT 1GB GDDR3		8640 Mtexels/sec
	Difference: 16056 (186%)

Pixel Rate

If running with a high screen resolution is important to you, then the GeForce 840M is a better choice, by a large margin. (explain)

GeForce 840M		8232 Mpixels/sec
GeForce 8600 GT 1GB GDDR3		4320 Mpixels/sec
	Difference: 3912 (91%)

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 largest amount of data (counted in MB per second) that can be transferred over the external memory interface in a second. It is calculated by multiplying the bus width by the speed of its memory. If the card has DDR RAM, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.

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

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly record to its local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of ROPs by the the core 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 rate also depends on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.