Radeon HD 4850 512MB vs Radeon HD 6850

Intro

Compare that to the Radeon HD 6850, which features GPU clock speed of 775 MHz, and 1024 MB of GDDR5 memory set to run at 1000 MHz through a 256-bit bus. It also is comprised of 960 SPUs, 48 Texture Address Units, and 32 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4850 512MB		110 Watts
Radeon HD 6850		127 Watts
	Difference: 17 Watts (15%)

Memory Bandwidth

The Radeon HD 6850, in theory, should be a lot faster than the Radeon HD 4850 512MB overall. (explain)

Radeon HD 6850		128000 MB/sec
Radeon HD 4850 512MB		63552 MB/sec
	Difference: 64448 (101%)

Texel Rate

The Radeon HD 6850 is a lot (approximately 49%) better at AF than the Radeon HD 4850 512MB. (explain)

Radeon HD 6850		37200 Mtexels/sec
Radeon HD 4850 512MB		25000 Mtexels/sec
	Difference: 12200 (49%)

Pixel Rate

The Radeon HD 6850 will be a lot (approximately 148%) faster with regards to full screen anti-aliasing than the Radeon HD 4850 512MB, and should be capable of handling higher resolutions without slowing down too much. (explain)

Radeon HD 6850		24800 Mpixels/sec
Radeon HD 4850 512MB		10000 Mpixels/sec
	Difference: 14800 (148%)

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 (counted in megabytes per second) that can be transferred past the external memory interface in a second. It's calculated by multiplying the interface width by its memory clock speed. If it uses DDR type RAM, it 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, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied per second. This number is calculated by multiplying the total texture units of the card by the core speed of the chip. The better the texel rate, 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 that the graphics chip could possibly record to the local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of Raster Operations Pipelines by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on many other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.