CitarThird-generation (CrossFireX)
A CrossFireX connection on a graphics card
Top view...
...and bottom view of a CrossFireX bridge connection
An example of CrossFire usage, with two Radeon HD 4850 cards (RV770 GPU)
With the release of the Radeon X1950 Pro (RV570 GPU), ATI has completely revised CrossFire's connection infrastructure to further eliminate the need for past Y-dongle/Master card and slave card configurations for CrossFire to operate. ATI's CrossFire connector is now a ribbon-like connector attached to the top of each graphics adapter, similar to nVidia's SLI bridges, but different in physical and logical natures.[5] As such, Master Cards no longer exist, and are not required for maximum performance. Two dongles can be used per card; these were put to full use with the release of CrossFireX. Radeon HD 2900 and HD 3000 series cards use the same ribbon connectors, but the HD 3800 series of cards only require one ribbon connector, to facilitate CrossFireX.[6] Unlike older series of Radeon cards, different HD 3800 series cards can be combined in CrossFire, each with separate clock control.
Since the release of the codenamed Spider desktop platform from AMD on November 19, 2007, the CrossFire setup has been updated with support for a maximum of four video cards with the 790FX chipset; the CrossFire branding was then changed to "ATI CrossFireX". The setup, which, according to internal testing by AMD, will bring at least 3.2x performance[citation needed] increase in several games and applications which required massive graphics capabilities of the computer system, is targeted to the enthusiast market.
A later development to the CrossFire infrastructure includes a dual GPU solution with on-board PCI Express bridge that was released in early 2008, the Radeon HD 3870 X2 and later in Radeon HD 4870 X2 graphics cards, featuring only one CrossFire connector for dual card, four GPU scalability.
An earlier CrossFireX and chipset compatibility chart is shown here:[7] The latest compatibility chart, as of March 2012, shows AMD 890, 990 and A75 chipsets—and many Intel chipsets including Z68 and X79 chipsets—as being compatible with CrossFireX; it also shows which GPU cards (in the HD 5750 / 6750 / 7750, HD 5770 / 6770 / 7770, and HD 58 / 59 / 68 / 69 / 78 / 79 series) may be paired with an external bridge (the new HD 7750 and HD 7770 cards may be paired without an external bridge).[8]
http://es.wikipedia.org/wiki/AMD_CrossFire
http://en.wikipedia.org/wiki/AMD_CrossFireX
¿Y dónde se pone ésto en tu modelo de gráfica que no lo veo?