Radeon HD 3870 X2 1GB vs Radeon RX 580

Intro

Compare that to the Radeon RX 580, which features a core clock speed of 1257 MHz and a GDDR5 memory speed of 2000 MHz. It also makes use of a 256-bit bus, and makes use of a 14 nm design. It is made up of 2304 SPUs, 144 TAUs, and 32 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

As far as performance goes, the Radeon RX 580 should in theory be quite a bit superior to the Radeon HD 3870 X2 1GB in general. (explain)

Radeon RX 580		262144 MB/sec
Radeon HD 3870 X2 1GB		144128 MB/sec
	Difference: 118016 (82%)

Texel Rate

The Radeon RX 580 should be quite a bit (more or less 586%) more effective at texture filtering than the Radeon HD 3870 X2 1GB. (explain)

Radeon RX 580		181008 Mtexels/sec
Radeon HD 3870 X2 1GB		26400 Mtexels/sec
	Difference: 154608 (586%)

Pixel Rate

If using a high screen resolution is important to you, then the Radeon RX 580 is superior to the Radeon HD 3870 X2 1GB, and very much so. (explain)

Radeon RX 580		40224 Mpixels/sec
Radeon HD 3870 X2 1GB		26400 Mpixels/sec
	Difference: 13824 (52%)

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 data (counted in megabytes per second) that can be moved past the external memory interface in a second. It's calculated by multiplying the card's bus width by its memory clock speed. If the card has DDR memory, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the better 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 can be applied in one second. This is worked out by multiplying the total texture units by the core clock speed of the chip. The better this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.

Pixel Rate: Pixel rate is the most pixels that the graphics card can possibly write to its local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Raster Operations Pipelines 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 output rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the max fill rate.