Radeon HD 3870 X2 512MB vs Radeon HD 5850

Intro

Compare those specs to the Radeon HD 5850, which makes use of a 40 nm design. AMD has set the core frequency at 725 MHz. The GDDR5 memory runs at a speed of 1000 MHz on this card. It features 1440(288x5) SPUs along with 72 Texture Address Units and 32 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

The Radeon HD 5850, in theory, should perform a small bit faster than the Radeon HD 3870 X2 512MB overall. (explain)

Radeon HD 5850		128000 MB/sec
Radeon HD 3870 X2 512MB		115200 MB/sec
	Difference: 12800 (11%)

Texel Rate

The Radeon HD 5850 is a lot (about 98%) more effective at anisotropic filtering than the Radeon HD 3870 X2 512MB. (explain)

Radeon HD 5850		52200 Mtexels/sec
Radeon HD 3870 X2 512MB		26400 Mtexels/sec
	Difference: 25800 (98%)

Pixel Rate

The Radeon HD 3870 X2 512MB will be a small bit (about 14%) better at AA than the Radeon HD 5850, and also capable of handling higher screen resolutions better. (explain)

Radeon HD 3870 X2 512MB		26400 Mpixels/sec
Radeon HD 5850		23200 Mpixels/sec
	Difference: 3200 (14%)

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 largest amount of data (counted in MB per second) that can be transported over the external memory interface in a second. It is calculated by multiplying the card's interface width by its memory speed. If the card has DDR RAM, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, 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 processed in one second. This figure is worked out by multiplying the total number of texture units of the card by the core speed of the chip. The higher the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly record to its local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on quite a few other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.