GeForce 9800 GX2 vs Radeon HD 7850

Intro

Compare those specifications to the Radeon HD 7850, which comes with core clock speeds of 860 MHz on the GPU, and 1200 MHz on the 2048 MB of GDDR5 memory. It features 1024 SPUs as well as 64 Texture Address Units and 32 Rasterization Operator Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7850		130 Watts
GeForce 9800 GX2		197 Watts
	Difference: 67 Watts (52%)

Memory Bandwidth

As far as performance goes, the Radeon HD 7850 should theoretically be a little bit superior to the GeForce 9800 GX2 overall. (explain)

Radeon HD 7850		153600 MB/sec
GeForce 9800 GX2		128000 MB/sec
	Difference: 25600 (20%)

Texel Rate

The GeForce 9800 GX2 will be a lot (more or less 40%) more effective at anisotropic filtering than the Radeon HD 7850. (explain)

GeForce 9800 GX2		76800 Mtexels/sec
Radeon HD 7850		55040 Mtexels/sec
	Difference: 21760 (40%)

Pixel Rate

If running with a high resolution is important to you, then the Radeon HD 7850 is a better choice, and very much so. (explain)

Radeon HD 7850		27520 Mpixels/sec
GeForce 9800 GX2		19200 Mpixels/sec
	Difference: 8320 (43%)

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 largest amount of data (measured in megabytes per second) that can be transferred past the external memory interface in a second. The number is worked out by multiplying the interface width by its memory clock speed. In the case of DDR RAM, it should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed in one second. This is worked out by multiplying the total texture units of the card by the core clock speed of the chip. The better the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of 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 output rate is also dependant on lots of other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.