GeForce 9800 GX2 vs GeForce GT 315

Intro

Compare all that to the GeForce GT 315, which comes with core clock speeds of 625 MHz on the GPU, and 790 MHz on the 512 MB of DDR3 memory. It features 48 SPUs along with 16 TAUs and 8 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 315		52 Watts
GeForce 9800 GX2		197 Watts
	Difference: 145 Watts (279%)

Memory Bandwidth

In theory, the GeForce 9800 GX2 should be quite a bit faster than the GeForce GT 315 overall. (explain)

GeForce 9800 GX2		128000 MB/sec
GeForce GT 315		25280 MB/sec
	Difference: 102720 (406%)

Texel Rate

The GeForce 9800 GX2 is a lot (about 668%) faster with regards to texture filtering than the GeForce GT 315. (explain)

GeForce 9800 GX2		76800 Mtexels/sec
GeForce GT 315		10000 Mtexels/sec
	Difference: 66800 (668%)

Pixel Rate

If running with high levels of AA is important to you, then the GeForce 9800 GX2 is the winner, by far. (explain)

GeForce 9800 GX2		19200 Mpixels/sec
GeForce GT 315		5000 Mpixels/sec
	Difference: 14200 (284%)

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: Bandwidth is the max amount of data (measured in MB per second) that can be transferred over the external memory interface in one second. It's worked out by multiplying the interface width by its memory clock speed. If the card has DDR type RAM, the result should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better 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 texture map elements (texels) that are processed in one second. This figure is worked out by multiplying the total texture units by the core speed of the chip. The better the texel rate, the better the card will be at handling 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 the graphics card could possibly record to its local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Raster Operations Pipelines 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 rate also depends on lots of other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the max fill rate.