GeForce 9800 GX2 vs Radeon HD 4790

Intro

Compare those specs to the Radeon HD 4790, which comes with core clock speeds of 600 MHz on the GPU, and 800 MHz on the 512 MB of GDDR5 memory. It features 640(128x5) SPUs as well as 32 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

As far as performance goes, the GeForce 9800 GX2 should theoretically be quite a bit better than the Radeon HD 4790 in general. (explain)

GeForce 9800 GX2		128000 MB/sec
Radeon HD 4790		102400 MB/sec
	Difference: 25600 (25%)

Texel Rate

The GeForce 9800 GX2 will be much (about 300%) faster with regards to AF than the Radeon HD 4790. (explain)

GeForce 9800 GX2		76800 Mtexels/sec
Radeon HD 4790		19200 Mtexels/sec
	Difference: 57600 (300%)

Pixel Rate

If using a high resolution is important to you, then the GeForce 9800 GX2 is a better choice, and very much so. (explain)

GeForce 9800 GX2		19200 Mpixels/sec
Radeon HD 4790		9600 Mpixels/sec
	Difference: 9600 (100%)

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 (counted in MB per second) that can be moved over the external memory interface within a second. It is worked out by multiplying the bus width by its memory clock speed. If it uses DDR memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher 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 can be processed in one second. This number is worked out by multiplying the total amount of texture units by the core clock speed of the chip. The higher the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.

Pixel Rate: Pixel rate is the most pixels the graphics card could possibly write to its local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.