GeForce 9800 GX2 vs GeForce GT 315

Intro

Compare those specifications to the GeForce GT 315, which has GPU core speed of 625 MHz, and 512 MB of DDR3 RAM set to run at 790 MHz through a 128-bit bus. It also is comprised of 48 Stream Processors, 16 TAUs, and 8 Raster Operation 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

Theoretically speaking, 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 much (about 668%) better at 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

The GeForce 9800 GX2 is a lot (more or less 284%) better at full screen anti-aliasing than the GeForce GT 315, and capable of handling higher screen resolutions while still performing well. (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: Memory bandwidth is the largest amount of data (in units of megabytes per second) that can be transferred past the external memory interface within a second. It is calculated by multiplying the card's interface width by its memory speed. If it uses DDR memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied in one 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 better the texel rate, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.

Pixel Rate: Pixel rate is the maximum number of pixels the video card could possibly record to its local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of colour ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.