GeForce 9600 GT 512MB vs GeForce GT 640 DDR3

Intro

Compare all that to the GeForce GT 640 DDR3, which comes with a core clock frequency of 900 MHz and a DDR3 memory speed of 1782 MHz. It also features a 128-bit memory bus, and uses a 28 nm design. It is made up of 384 SPUs, 32 Texture Address Units, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 640 DDR3		65 Watts
GeForce 9600 GT 512MB		95 Watts
	Difference: 30 Watts (46%)

Memory Bandwidth

The GeForce 9600 GT 512MB should theoretically perform a small bit faster than the GeForce GT 640 DDR3 in general. (explain)

GeForce 9600 GT 512MB		57600 MB/sec
GeForce GT 640 DDR3		57024 MB/sec
	Difference: 576 (1%)

Texel Rate

The GeForce GT 640 DDR3 is a lot (more or less 38%) more effective at anisotropic filtering than the GeForce 9600 GT 512MB. (explain)

GeForce GT 640 DDR3		28800 Mtexels/sec
GeForce 9600 GT 512MB		20800 Mtexels/sec
	Difference: 8000 (38%)

Pixel Rate

The GeForce GT 640 DDR3 is quite a bit (more or less 38%) more effective at FSAA than the GeForce 9600 GT 512MB, and also will be able to handle higher resolutions better. (explain)

GeForce GT 640 DDR3		14400 Mpixels/sec
GeForce 9600 GT 512MB		10400 Mpixels/sec
	Difference: 4000 (38%)

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 max amount of information (measured in megabytes per second) that can be transferred over the external memory interface in one 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 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied in one second. This is calculated 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 processed per second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly record to its local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the number of Render Output Units by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.