GeForce GTX 460 2GB vs Radeon HD 4890 1GB

Intro

Compare those specifications to the Radeon HD 4890 1GB, which comes with a clock speed of 1000 MHz and a GDDR5 memory frequency of 975 MHz. It also uses a 256-bit bus, and makes use of a 55 nm design. It features 800(160x5) SPUs, 40 Texture Address Units, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 460 2GB		160 Watts
Radeon HD 4890 1GB		190 Watts
	Difference: 30 Watts (19%)

Memory Bandwidth

Theoretically, the Radeon HD 4890 1GB should perform a bit faster than the GeForce GTX 460 2GB overall. (explain)

Radeon HD 4890 1GB		124800 MB/sec
GeForce GTX 460 2GB		115200 MB/sec
	Difference: 9600 (8%)

Texel Rate

The Radeon HD 4890 1GB is a small bit (about 6%) better at AF than the GeForce GTX 460 2GB. (explain)

Radeon HD 4890 1GB		40000 Mtexels/sec
GeForce GTX 460 2GB		37800 Mtexels/sec
	Difference: 2200 (6%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the GeForce GTX 460 2GB is the winner, and very much so. (explain)

GeForce GTX 460 2GB		21600 Mpixels/sec
Radeon HD 4890 1GB		16000 Mpixels/sec
	Difference: 5600 (35%)

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 largest amount of data (measured in MB per second) that can be transferred past the external memory interface within a second. It's worked out by multiplying the interface width by its memory clock speed. In the case of DDR memory, it must 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 are applied per 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 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 amount of pixels the video card could possibly record to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the number of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on quite a few other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the max fill rate.