GeForce 9400 GT 256MB vs GeForce GTX 580 3GB

Intro

Compare all of that to the GeForce GTX 580 3GB, which has a clock frequency of 772 MHz and a GDDR5 memory speed of 1002 MHz. It also uses a 384-bit memory bus, and makes use of a 40 nm design. It is comprised of 512 SPUs, 64 Texture Address Units, and 48 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 9400 GT 256MB		50 Watts
GeForce GTX 580 3GB		244 Watts
	Difference: 194 Watts (388%)

Memory Bandwidth

Theoretically speaking, the GeForce GTX 580 3GB should be much faster than the GeForce 9400 GT 256MB overall. (explain)

GeForce GTX 580 3GB		192384 MB/sec
GeForce 9400 GT 256MB		12800 MB/sec
	Difference: 179584 (1403%)

Texel Rate

The GeForce GTX 580 3GB is a lot (about 1023%) more effective at AF than the GeForce 9400 GT 256MB. (explain)

GeForce GTX 580 3GB		49408 Mtexels/sec
GeForce 9400 GT 256MB		4400 Mtexels/sec
	Difference: 45008 (1023%)

Pixel Rate

The GeForce GTX 580 3GB is much (approximately 1584%) faster with regards to AA than the GeForce 9400 GT 256MB, and also will be able to handle higher screen resolutions without losing too much performance. (explain)

GeForce GTX 580 3GB		37056 Mpixels/sec
GeForce 9400 GT 256MB		2200 Mpixels/sec
	Difference: 34856 (1584%)

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 (in units of MB per second) that can be transported past the external memory interface in one second. It is calculated by multiplying the bus width by its memory speed. If it uses DDR type RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better 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 amount of texture map elements (texels) that can be processed in one second. This number is calculated by multiplying the total number of texture units by the core speed of the chip. The higher the texel rate, 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 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 amount of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.