GeForce 9800 GX2 vs Radeon HD 5850

Intro

Compare those specifications to the Radeon HD 5850, which uses a 40 nm design. AMD has set the core frequency at 725 MHz. The GDDR5 memory runs at a frequency of 1000 MHz on this particular card. It features 1440(288x5) SPUs as well as 72 TAUs and 32 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 5850		151 Watts
GeForce 9800 GX2		197 Watts
	Difference: 46 Watts (30%)

Memory Bandwidth

Both cards have exactly the same bandwidth, so theoretically they should perform the same. (explain)

Texel Rate

The GeForce 9800 GX2 is quite a bit (more or less 47%) better at anisotropic filtering than the Radeon HD 5850. (explain)

GeForce 9800 GX2		76800 Mtexels/sec
Radeon HD 5850		52200 Mtexels/sec
	Difference: 24600 (47%)

Pixel Rate

If running with a high screen resolution is important to you, then the Radeon HD 5850 is a better choice, by a large margin. (explain)

Radeon HD 5850		23200 Mpixels/sec
GeForce 9800 GX2		19200 Mpixels/sec
	Difference: 4000 (21%)

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 information (in units of MB per second) that can be transferred across the external memory interface within a second. It's worked out by multiplying the interface width by its memory speed. If it uses DDR type memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, 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 per second. This is calculated by multiplying the total amount of texture units of the card by the core speed of the chip. The better the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels the video card can possibly write to its local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.