Radeon HD 3850 X2 vs Radeon HD 7870 XT

Intro

Compare all that to the Radeon HD 7870 XT, which features a core clock frequency of 925 MHz and a GDDR5 memory speed of 1500 MHz. It also uses a 256-bit bus, and makes use of a 28 nm design. It is comprised of 1536 SPUs, 96 Texture Address Units, and 32 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

As far as performance goes, the Radeon HD 7870 XT should theoretically be much better than the Radeon HD 3850 X2 in general. (explain)

Radeon HD 7870 XT		192000 MB/sec
Radeon HD 3850 X2		105984 MB/sec
	Difference: 86016 (81%)

Texel Rate

The Radeon HD 7870 XT should be much (about 315%) better at texture filtering than the Radeon HD 3850 X2. (explain)

Radeon HD 7870 XT		88800 Mtexels/sec
Radeon HD 3850 X2		21376 Mtexels/sec
	Difference: 67424 (315%)

Pixel Rate

If running with a high screen resolution is important to you, then the Radeon HD 7870 XT is superior to the Radeon HD 3850 X2, and very much so. (explain)

Radeon HD 7870 XT		29600 Mpixels/sec
Radeon HD 3850 X2		21376 Mpixels/sec
	Difference: 8224 (38%)

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 largest amount of information (in units of MB per second) that can be moved over the external memory interface within a second. It is worked out by multiplying the bus width by its memory clock speed. If it uses DDR memory, it must be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied per second. This number is worked out by multiplying the total texture units of the card by the core speed of the chip. The higher this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.

Pixel Rate: Pixel rate is the maximum amount of pixels the video card could possibly record to its local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate is also dependant on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.