Geforce GTX 680 vs Radeon HD 3870 X2 1GB

Intro

Compare all of that to the Radeon HD 3870 X2 1GB, which comes with a core clock speed of 825 MHz and a GDDR4 memory frequency of 1126 MHz. It also uses a 256-bit bus, and makes use of a 55 nm design. It features 320(64x5) SPUs, 16 Texture Address Units, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

In theory, the Geforce GTX 680 should be 33% faster than the Radeon HD 3870 X2 1GB in general, due to its greater data rate. (explain)

Geforce GTX 680		192256 MB/sec
Radeon HD 3870 X2 1GB		144128 MB/sec
	Difference: 48128 (33%)

Texel Rate

The Geforce GTX 680 should be much (more or less 388%) faster with regards to texture filtering than the Radeon HD 3870 X2 1GB. (explain)

Geforce GTX 680		128768 Mtexels/sec
Radeon HD 3870 X2 1GB		26400 Mtexels/sec
	Difference: 102368 (388%)

Pixel Rate

If using a high resolution is important to you, then the Geforce GTX 680 is the winner, by far. (explain)

Geforce GTX 680		32192 Mpixels/sec
Radeon HD 3870 X2 1GB		26400 Mpixels/sec
	Difference: 5792 (22%)

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 data (measured in MB per second) that can be moved across the external memory interface within a second. It's calculated by multiplying the card's bus width by its memory speed. In the case of DDR memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

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

Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card can possibly record to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the amount of Raster Operations Pipelines by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the max fill rate.