GeForce 9800 GT 512MB vs GeForce GTX 660

Intro

Compare those specifications to the GeForce GTX 660, which comes with a clock speed of 980 MHz and a GDDR5 memory frequency of 1502 MHz. It also uses a 192-bit memory bus, and uses a 28 nm design. It features 960 SPUs, 80 Texture Address Units, and 24 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 9800 GT 512MB		105 Watts
GeForce GTX 660		140 Watts
	Difference: 35 Watts (33%)

Memory Bandwidth

Theoretically speaking, the GeForce GTX 660 is 150% faster than the GeForce 9800 GT 512MB overall, because of its greater bandwidth. (explain)

GeForce GTX 660		144192 MB/sec
GeForce 9800 GT 512MB		57600 MB/sec
	Difference: 86592 (150%)

Texel Rate

The GeForce GTX 660 is quite a bit (approximately 133%) more effective at anisotropic filtering than the GeForce 9800 GT 512MB. (explain)

GeForce GTX 660		78400 Mtexels/sec
GeForce 9800 GT 512MB		33600 Mtexels/sec
	Difference: 44800 (133%)

Pixel Rate

The GeForce GTX 660 will be a lot (more or less 145%) better at full screen anti-aliasing than the GeForce 9800 GT 512MB, and able to handle higher screen resolutions better. (explain)

GeForce GTX 660		23520 Mpixels/sec
GeForce 9800 GT 512MB		9600 Mpixels/sec
	Difference: 13920 (145%)

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 megabytes per second) that can be moved past the external memory interface in one second. It's calculated by multiplying the bus width by its memory clock speed. If the card has DDR RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher 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 amount of texture map elements (texels) that can be processed in one second. This is calculated by multiplying the total texture units by the core speed of the chip. The higher the texel rate, the better the video 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 maximum number of pixels the graphics card could possibly write to its local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the number of colour ROPs by the the core 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 rate is also dependant on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.