GeForce 9800 GX2 vs GeForce GTX 650

Intro

Compare those specs to the GeForce GTX 650, which makes use of a 28 nm design. nVidia has set the core speed at 1058 MHz. The GDDR5 memory works at a speed of 1250 MHz on this card. It features 384 SPUs along with 32 TAUs and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 650		64 Watts
GeForce 9800 GX2		197 Watts
	Difference: 133 Watts (208%)

Memory Bandwidth

Theoretically speaking, the GeForce 9800 GX2 is 60% faster than the GeForce GTX 650 in general, because of its greater data rate. (explain)

GeForce 9800 GX2		128000 MB/sec
GeForce GTX 650		80000 MB/sec
	Difference: 48000 (60%)

Texel Rate

The GeForce 9800 GX2 should be much (about 127%) more effective at AF than the GeForce GTX 650. (explain)

GeForce 9800 GX2		76800 Mtexels/sec
GeForce GTX 650		33856 Mtexels/sec
	Difference: 42944 (127%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the GeForce 9800 GX2 is the winner, but it probably won't make a huge difference. (explain)

GeForce 9800 GX2		19200 Mpixels/sec
GeForce GTX 650		16928 Mpixels/sec
	Difference: 2272 (13%)

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.

One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the max amount of data (measured in megabytes per second) that can be moved over the external memory interface within a second. It is calculated by multiplying the card's bus width by its memory clock speed. If it uses DDR type memory, it should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the bandwidth is, the better 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 texture map elements (texels) that can be processed per second. This figure is worked out by multiplying the total number 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 texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.

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