Radeon HD 3870 X2 1GB vs Radeon HD 5850

Intro

Compare all of that to the Radeon HD 5850, which comes with core speeds of 725 MHz on the GPU, and 1000 MHz on the 1024 MB of GDDR5 RAM. It features 1440(288x5) SPUs along with 72 Texture Address Units and 32 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

The Radeon HD 3870 X2 1GB should in theory be just a bit faster than the Radeon HD 5850 in general. (explain)

Radeon HD 3870 X2 1GB		144128 MB/sec
Radeon HD 5850		128000 MB/sec
	Difference: 16128 (13%)

Texel Rate

The Radeon HD 5850 should be much (about 98%) faster with regards to texture filtering than the Radeon HD 3870 X2 1GB. (explain)

Radeon HD 5850		52200 Mtexels/sec
Radeon HD 3870 X2 1GB		26400 Mtexels/sec
	Difference: 25800 (98%)

Pixel Rate

If using a high resolution is important to you, then the Radeon HD 3870 X2 1GB is a better choice, though not by far. (explain)

Radeon HD 3870 X2 1GB		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 max amount of information (measured in megabytes per second) that can be moved across the external memory interface in one second. It's worked out by multiplying the bus width by its memory clock speed. If the card has 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 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 number of texture map elements (texels) that can be processed per second. This figure is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The higher this number, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly write to the local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of ROPs 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 also depends on quite a few other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.