Geforce GTX 680 vs Radeon HD 4850 1GB

Intro

Compare those specs to the Radeon HD 4850 1GB, which features a core clock speed of 625 MHz and a GDDR4 memory speed of 993 MHz. It also features a 256-bit bus, and uses a 55 nm design. It is made up of 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)

Radeon HD 4850 1GB		110 Watts
Geforce GTX 680		195 Watts
	Difference: 85 Watts (77%)

Memory Bandwidth

The Geforce GTX 680 should in theory perform quite a bit faster than the Radeon HD 4850 1GB in general. (explain)

Geforce GTX 680		192256 MB/sec
Radeon HD 4850 1GB		63552 MB/sec
	Difference: 128704 (203%)

Texel Rate

The Geforce GTX 680 will be much (approximately 415%) faster with regards to AF than the Radeon HD 4850 1GB. (explain)

Geforce GTX 680		128768 Mtexels/sec
Radeon HD 4850 1GB		25000 Mtexels/sec
	Difference: 103768 (415%)

Pixel Rate

The Geforce GTX 680 is a lot (about 222%) faster with regards to FSAA than the Radeon HD 4850 1GB, and will be capable of handling higher resolutions without slowing down too much. (explain)

Geforce GTX 680		32192 Mpixels/sec
Radeon HD 4850 1GB		10000 Mpixels/sec
	Difference: 22192 (222%)

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 data (counted in MB per second) that can be transferred across the external memory interface in a second. It is calculated by multiplying the card's bus width by the speed of its memory. In the case of DDR type RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed per second. This is worked out by multiplying the total number of texture units of the card by the core clock 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 in a second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is worked out 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 outputting the pixels (image) to the screen. The actual pixel fill rate also depends on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.