Radeon HD 3870 X2 1GB vs Radeon R9 285

Intro

Compare those specs to the Radeon R9 285, which uses a 28 nm design. AMD has clocked the core frequency at 918 MHz. The GDDR5 memory runs at a frequency of 1375 MHz on this particular card. It features 1792 SPUs along with 112 TAUs and 32 Rasterization Operator Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Memory Bandwidth

The Radeon R9 285 should in theory be much faster than the Radeon HD 3870 X2 1GB overall. (explain)

Radeon R9 285		176000 MB/sec
Radeon HD 3870 X2 1GB		144128 MB/sec
	Difference: 31872 (22%)

Texel Rate

The Radeon R9 285 should be quite a bit (approximately 289%) faster with regards to texture filtering than the Radeon HD 3870 X2 1GB. (explain)

Radeon R9 285		102816 Mtexels/sec
Radeon HD 3870 X2 1GB		26400 Mtexels/sec
	Difference: 76416 (289%)

Pixel Rate

If running with a high resolution is important to you, then the Radeon R9 285 is the winner, though only just barely. (explain)

Radeon R9 285		29376 Mpixels/sec
Radeon HD 3870 X2 1GB		26400 Mpixels/sec
	Difference: 2976 (11%)

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: Bandwidth is the maximum amount of information (counted in megabytes per second) that can be transferred past the external memory interface within a second. The number is worked out by multiplying the bus width by its memory speed. If the card has DDR RAM, the result should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed in one second. This is calculated by multiplying the total texture units by the core clock speed of the chip. The better this number, 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 the graphics card can possibly write to its local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of ROPs by the the card's clock speed. 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, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.