GeForce 840M vs GeForce 8600 GT 256MB DDR2

Intro

Compare those specs to the GeForce 8600 GT 256MB DDR2, which features GPU clock speed of 540 MHz, and 256 MB of DDR2 RAM set to run at 400 MHz through a 128-bit bus. It also features 32 SPUs, 16 TAUs, and 8 Raster Operation Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 840M		30 Watts
GeForce 8600 GT 256MB DDR2		47 Watts
	Difference: 17 Watts (57%)

Memory Bandwidth

The GeForce 840M should theoretically perform a lot faster than the GeForce 8600 GT 256MB DDR2 in general. (explain)

GeForce 840M		16000 MB/sec
GeForce 8600 GT 256MB DDR2		12800 MB/sec
	Difference: 3200 (25%)

Texel Rate

The GeForce 840M will be much (approximately 186%) more effective at AF than the GeForce 8600 GT 256MB DDR2. (explain)

GeForce 840M		24696 Mtexels/sec
GeForce 8600 GT 256MB DDR2		8640 Mtexels/sec
	Difference: 16056 (186%)

Pixel Rate

The GeForce 840M will be much (approximately 91%) more effective at FSAA than the GeForce 8600 GT 256MB DDR2, and capable of handling higher resolutions without slowing down too much. (explain)

GeForce 840M		8232 Mpixels/sec
GeForce 8600 GT 256MB DDR2		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 information (in units of MB per second) that can be moved past the external memory interface within a second. The number is worked out by multiplying the bus width by its memory speed. If the card has DDR memory, it should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the bandwidth is, 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 number of texture map elements (texels) that can be processed in one second. This is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The higher the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

Pixel Rate: Pixel rate is the most pixels the video card could possibly record to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.