Radeon HD 3870 1GB vs Radeon HD 3870 X2 512MB

Intro

Compare those specs to the Radeon HD 3870 X2 512MB, which uses a 55 nm design. AMD has set the core frequency at 825 MHz. The GDDR3 memory is set to run at a speed of 900 MHz on this specific card. It features 320(64x5) SPUs as well as 16 TAUs and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

As far as performance goes, the Radeon HD 3870 X2 512MB should theoretically be quite a bit better than the Radeon HD 3870 1GB in general. (explain)

Radeon HD 3870 X2 512MB		115200 MB/sec
Radeon HD 3870 1GB		72000 MB/sec
	Difference: 43200 (60%)

Texel Rate

The Radeon HD 3870 X2 512MB is much (about 113%) faster with regards to AF than the Radeon HD 3870 1GB. (explain)

Radeon HD 3870 X2 512MB		26400 Mtexels/sec
Radeon HD 3870 1GB		12400 Mtexels/sec
	Difference: 14000 (113%)

Pixel Rate

If using lots of anti-aliasing is important to you, then the Radeon HD 3870 X2 512MB is superior to the Radeon HD 3870 1GB, by far. (explain)

Radeon HD 3870 X2 512MB		26400 Mpixels/sec
Radeon HD 3870 1GB		12400 Mpixels/sec
	Difference: 14000 (113%)

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 data (measured in megabytes per second) that can be transported past the external memory interface in a second. It is calculated by multiplying the card's interface width by its memory clock speed. If the card has DDR RAM, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

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