GeForce 840M vs GeForce 8600 GT 1GB DDR2

Intro

Compare that to the GeForce 8600 GT 1GB DDR2, which makes use of a 80 nm design. nVidia has set the core frequency at 540 MHz. The DDR2 memory is set to run at a frequency of 400 MHz on this particular model. It features 32 SPUs as well as 16 TAUs 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 DDR2		47 Watts
	Difference: 17 Watts (57%)

Memory Bandwidth

The GeForce 840M should theoretically perform a lot faster than the GeForce 8600 GT 1GB DDR2 overall. (explain)

GeForce 840M		16000 MB/sec
GeForce 8600 GT 1GB DDR2		12800 MB/sec
	Difference: 3200 (25%)

Texel Rate

The GeForce 840M should be quite a bit (about 186%) faster with regards to texture filtering than the GeForce 8600 GT 1GB DDR2. (explain)

GeForce 840M		24696 Mtexels/sec
GeForce 8600 GT 1GB DDR2		8640 Mtexels/sec
	Difference: 16056 (186%)

Pixel Rate

The GeForce 840M should be quite a bit (approximately 91%) more effective at FSAA than the GeForce 8600 GT 1GB DDR2, and will be capable of handling higher screen resolutions more effectively. (explain)

GeForce 840M		8232 Mpixels/sec
GeForce 8600 GT 1GB 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 maximum amount of data (counted in megabytes per second) that can be moved over the external memory interface in one second. It is worked out by multiplying the bus width by its memory speed. In the case of DDR RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

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

Pixel Rate: Pixel rate is the maximum amount of pixels the video card could possibly record to the local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the number of ROPs by the the card's clock speed. 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 output rate also depends on quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.