Radeon HD 3870 X2 1GB vs Radeon HD 7870

Intro

Compare all of that to the Radeon HD 7870, which uses a 28 nm design. AMD has clocked the core frequency at 1000 MHz. The GDDR5 RAM is set to run at a speed of 1200 MHz on this model. It features 1280 SPUs as well as 80 TAUs and 32 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Performance-wise, the Radeon HD 7870 should in theory be a small bit superior to the Radeon HD 3870 X2 1GB overall. (explain)

Radeon HD 7870		153600 MB/sec
Radeon HD 3870 X2 1GB		144128 MB/sec
	Difference: 9472 (7%)

Texel Rate

The Radeon HD 7870 should be much (more or less 203%) faster with regards to texture filtering than the Radeon HD 3870 X2 1GB. (explain)

Radeon HD 7870		80000 Mtexels/sec
Radeon HD 3870 X2 1GB		26400 Mtexels/sec
	Difference: 53600 (203%)

Pixel Rate

If running with a high screen resolution is important to you, then the Radeon HD 7870 is a better choice, and very much so. (explain)

Radeon HD 7870		32000 Mpixels/sec
Radeon HD 3870 X2 1GB		26400 Mpixels/sec
	Difference: 5600 (21%)

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 max amount of data (measured in megabytes per second) that can be moved past the external memory interface in one second. The number is worked out by multiplying the card's interface width by the speed of its memory. In the case of DDR type RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better 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 amount of 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 clock speed of the chip. The better this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card can possibly record to its local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the amount of colour ROPs 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 is also dependant on lots of other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.