GeForce 8800 Ultra vs Radeon HD 4850 X2 512MB

Intro

Compare those specifications to the Radeon HD 4850 X2 512MB, which features a clock frequency of 625 MHz and a GDDR3 memory speed of 993 MHz. It also makes use of a 256-bit bus, and uses a 55 nm design. It features 800(160x5) SPUs, 40 Texture Address Units, and 16 ROPs.

Display Graphs

Hide Graphs

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

Performance-wise, the Radeon HD 4850 X2 512MB should in theory be quite a bit better than the GeForce 8800 Ultra in general. (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 much (more or less 28%) better at anisotropic 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 a lot (about 36%) faster with regards to full screen anti-aliasing than the GeForce 8800 Ultra, and also should be capable of handling higher screen resolutions while still performing well. (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: Bandwidth is the maximum amount of data (measured in megabytes per second) that can be transferred over the external memory interface within a second. It's calculated by multiplying the bus width by the speed of its memory. If it uses DDR RAM, it should be multiplied by 2 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 number of texture map elements (texels) that are applied in one second. This is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The better this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.

Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly write to its local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number 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 fill rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.