Radeon HD 3850 512MB vs Radeon HD 4850 X2 512MB

Intro

Compare those specifications to the Radeon HD 4850 X2 512MB, which has a GPU core clock speed of 625 MHz, and 512 MB of GDDR3 memory set to run at 993 MHz through a 256-bit bus. It also is made up of 800(160x5) Stream Processors, 40 Texture Address Units, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 3850 512MB		75 Watts
Radeon HD 4850 X2 512MB		250 Watts
	Difference: 175 Watts (233%)

Memory Bandwidth

The Radeon HD 4850 X2 512MB should in theory be much faster than the Radeon HD 3850 512MB in general. (explain)

Radeon HD 4850 X2 512MB		127104 MB/sec
Radeon HD 3850 512MB		52992 MB/sec
	Difference: 74112 (140%)

Texel Rate

The Radeon HD 4850 X2 512MB will be quite a bit (approximately 368%) faster with regards to AF than the Radeon HD 3850 512MB. (explain)

Radeon HD 4850 X2 512MB		50000 Mtexels/sec
Radeon HD 3850 512MB		10688 Mtexels/sec
	Difference: 39312 (368%)

Pixel Rate

If using a high resolution is important to you, then the Radeon HD 4850 X2 512MB is the winner, by a large margin. (explain)

Radeon HD 4850 X2 512MB		20000 Mpixels/sec
Radeon HD 3850 512MB		10688 Mpixels/sec
	Difference: 9312 (87%)

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.

One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the maximum amount of data (counted in megabytes per second) that can be moved across the external memory interface within a second. It is calculated by multiplying the card's bus width by its memory speed. If it uses DDR memory, it should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied in one second. This figure is worked out by multiplying the total texture units by the core 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 processed in one second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly record to its local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on lots of other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.