GeForce 8800 Ultra vs Radeon HD 4890 2GB

Intro

Compare all that to the Radeon HD 4890 2GB, which uses a 55 nm design. AMD has clocked the core speed at 1000 MHz. The GDDR5 memory runs at a speed of 975 MHz on this model. It features 800(160x5) SPUs along with 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 4890 2GB		190 Watts
	Difference: 19 Watts (11%)

Memory Bandwidth

Performance-wise, the Radeon HD 4890 2GB should theoretically be a small bit better than the GeForce 8800 Ultra in general. (explain)

Radeon HD 4890 2GB		124800 MB/sec
GeForce 8800 Ultra		103680 MB/sec
	Difference: 21120 (20%)

Texel Rate

The Radeon HD 4890 2GB will be a small bit (more or less 2%) faster with regards to anisotropic filtering than the GeForce 8800 Ultra. (explain)

Radeon HD 4890 2GB		40000 Mtexels/sec
GeForce 8800 Ultra		39168 Mtexels/sec
	Difference: 832 (2%)

Pixel Rate

The Radeon HD 4890 2GB will be just a bit (approximately 9%) faster with regards to anti-aliasing than the GeForce 8800 Ultra, and also capable of handling higher resolutions without slowing down too much. (explain)

Radeon HD 4890 2GB		16000 Mpixels/sec
GeForce 8800 Ultra		14688 Mpixels/sec
	Difference: 1312 (9%)

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.

Price Comparison

Specifications

Memory Bandwidth: Bandwidth is the maximum amount of information (counted in MB per second) that can be transported past the external memory interface within a second. It is calculated by multiplying the interface width by its memory clock speed. If it uses DDR RAM, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed in one second. This number is calculated by multiplying the total number of texture units 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 the 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 card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.