Radeon HD 3870 X2 512MB vs Radeon HD 6770

Intro

Compare all that to the Radeon HD 6770, which makes use of a 40 nm design. AMD has clocked the core frequency at 900 MHz. The GDDR5 RAM is set to run at a speed of 1050 MHz on this specific card. It features 800 SPUs along with 40 Texture Address Units and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

In theory, the Radeon HD 3870 X2 512MB should be 71% quicker than the Radeon HD 6770 in general, because of its higher bandwidth. (explain)

Radeon HD 3870 X2 512MB		115200 MB/sec
Radeon HD 6770		67200 MB/sec
	Difference: 48000 (71%)

Texel Rate

The Radeon HD 6770 should be quite a bit (approximately 36%) more effective at texture filtering than the Radeon HD 3870 X2 512MB. (explain)

Radeon HD 6770		36000 Mtexels/sec
Radeon HD 3870 X2 512MB		26400 Mtexels/sec
	Difference: 9600 (36%)

Pixel Rate

The Radeon HD 3870 X2 512MB should be quite a bit (more or less 83%) better at FSAA than the Radeon HD 6770, and also capable of handling higher screen resolutions better. (explain)

Radeon HD 3870 X2 512MB		26400 Mpixels/sec
Radeon HD 6770		14400 Mpixels/sec
	Difference: 12000 (83%)

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 largest amount of data (measured in megabytes per second) that can be transferred across the external memory interface in one second. It is calculated by multiplying the card's interface width by its memory speed. If the card has DDR RAM, it should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster 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 texture map elements (texels) that are applied per second. This number is worked out by multiplying the total number of texture units of the card by the core speed of the chip. The better the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card could possibly record to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends 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.