GeForce GTX 460 1GB vs Radeon HD 4890 2GB

Intro

Compare that to the Radeon HD 4890 2GB, which features a clock frequency of 1000 MHz and a GDDR5 memory speed of 975 MHz. It also uses a 256-bit memory bus, and makes use of 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 GTX 460 1GB		160 Watts
Radeon HD 4890 2GB		190 Watts
	Difference: 30 Watts (19%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 4890 2GB should be 8% quicker than the GeForce GTX 460 1GB in general, because of its higher bandwidth. (explain)

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

Texel Rate

The Radeon HD 4890 2GB is a small bit (more or less 6%) better at anisotropic filtering than the GeForce GTX 460 1GB. (explain)

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

Pixel Rate

If using a high screen resolution is important to you, then the GeForce GTX 460 1GB is a better choice, by far. (explain)

GeForce GTX 460 1GB		21600 Mpixels/sec
Radeon HD 4890 2GB		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: Memory bandwidth is the max amount of information (in units of MB per second) that can be transferred past the external memory interface in one second. The number is calculated by multiplying the card's interface width by the speed of its memory. If the card has DDR memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen 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 clock speed of the chip. The better this number, the better the card will be at 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 can possibly write to the local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the number of Raster Operations Pipelines 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, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.