GeForce 8800 Ultra vs Radeon HD 4850 X2 512MB

Intro

Compare those specs to the Radeon HD 4850 X2 512MB, which features a GPU core clock speed of 625 MHz, and 512 MB of GDDR3 memory set to run at 993 MHz through a 256-bit bus. It also is made up of 800(160x5) SPUs, 40 TAUs, and 16 Raster Operation Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8800 Ultra		171 Watts
Radeon HD 4850 X2 512MB		250 Watts
	Difference: 79 Watts (46%)

Memory Bandwidth

In theory, the Radeon HD 4850 X2 512MB is 23% faster than the GeForce 8800 Ultra in general, because of its greater data rate. (explain)

Radeon HD 4850 X2 512MB		127104 MB/sec
GeForce 8800 Ultra		103680 MB/sec
	Difference: 23424 (23%)

Texel Rate

The Radeon HD 4850 X2 512MB will be a lot (more or less 28%) better at texture filtering than the GeForce 8800 Ultra. (explain)

Radeon HD 4850 X2 512MB		50000 Mtexels/sec
GeForce 8800 Ultra		39168 Mtexels/sec
	Difference: 10832 (28%)

Pixel Rate

The Radeon HD 4850 X2 512MB should be quite a bit (more or less 36%) more effective at AA than the GeForce 8800 Ultra, and able to handle higher resolutions without losing too much performance. (explain)

Radeon HD 4850 X2 512MB		20000 Mpixels/sec
GeForce 8800 Ultra		14688 Mpixels/sec
	Difference: 5312 (36%)

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 (measured in MB per second) that can be transferred past the external memory interface in a second. It is calculated by multiplying the bus width by its memory speed. If the card has DDR type RAM, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied per second. This number is worked out by multiplying the total texture units by the core speed of the chip. The higher this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly write to its local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the number of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on lots of other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.