GeForce 8800 Ultra vs Radeon HD 4870 X2

Intro

Compare all of that to the Radeon HD 4870 X2, which uses a 55 nm design. AMD has clocked the core speed at 750 MHz. The GDDR5 RAM works at a speed of 900 MHz on this specific model. It features 800(160x5) SPUs along with 40 TAUs and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8800 Ultra		171 Watts
Radeon HD 4870 X2		350 Watts
	Difference: 179 Watts (105%)

Memory Bandwidth

The Radeon HD 4870 X2 should in theory be much faster than the GeForce 8800 Ultra in general. (explain)

Radeon HD 4870 X2		230400 MB/sec
GeForce 8800 Ultra		103680 MB/sec
	Difference: 126720 (122%)

Texel Rate

The Radeon HD 4870 X2 should be much (more or less 53%) better at AF than the GeForce 8800 Ultra. (explain)

Radeon HD 4870 X2		60000 Mtexels/sec
GeForce 8800 Ultra		39168 Mtexels/sec
	Difference: 20832 (53%)

Pixel Rate

If using lots of anti-aliasing is important to you, then the Radeon HD 4870 X2 is the winner, by a large margin. (explain)

Radeon HD 4870 X2		24000 Mpixels/sec
GeForce 8800 Ultra		14688 Mpixels/sec
	Difference: 9312 (63%)

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 information (measured in megabytes per second) that can be transferred over the external memory interface in one second. It's calculated by multiplying the interface width by the speed of its memory. If the card has DDR memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, 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 number of texture map elements (texels) that are applied per second. This number is worked out by multiplying the total texture units of the card by the core clock 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 applied in a 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. 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 filling the screen with pixels (the image). The actual pixel output rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.