The second CrossFire generation, called Native CrossFire, solved the two main problems found on previous generation: the requirement of a “master”card (as the composition engine is now embedded on the graphics chip of all video cards that support Native CrossFire and CrossFireX) and the cable issue, using a bridge just like SLI for high-end cards. Actually two bridges are needed to connect the cards, as each card has two connectors.

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Figure 9: Native CrossFire connectors on a Radeon video card.

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Figure 10: Native CrossFire bridge. You need two of them.

For mainstream cards ATI also decided to use the same approach used by NVIDIA: the cards are connected through the PCI Express bus, not requiring an external bridge.

Native CrossFire increased the maximum resolution to 2560x2048.

In the table below you have a list of all possible combinations of video cards using Native CrossFire and a column indicating if the bridges are necessary or not. So you cannot hook up your Radeon HD 2900 Pro to a Radeon HD 2600 XT, for example.

First Video Card	Second Video Card	Bridges Required
Radeon HD 3870 X2 Radeon HD 3870 Radeon HD 3850	Radeon HD 3870 X2 Radeon HD 3870 Radeon HD 3850	Yes
Radeon HD 3650	Radeon HD 3650	Yes
Radeon HD 3470 Radeon HD 3450	Radeon HD 3470 Radeon HD 3450	Yes
Radeon HD 2900 XT Radeon HD 2900 Pro	Radeon HD 2900 XT Radeon HD 2900 Pro	Yes
Radeon HD 2600 XT Radeon HD 2600 Pro	Radeon HD 2600 XT Radeon HD 2600 Pro	Yes
Radeon HD 2400 XT Radeon HD 2400 Pro	Radeon HD 2400 XT Radeon HD 2400 Pro	Yes
Radeon X1950 Pro	Radeon X1950 Pro	Yes
Radeon X1950 GT	Radeon X1950 GT	Yes
Radeon X1650 XT	Radeon X1650 XT	Yes
Radeon X1650 Pro Radeon X1650 Radeon X1600 XT Radeon X1600 Pro	Radeon X1650 Pro Radeon X1650 Radeon X1600 XT Radeon X1600 Pro	No
Radeon X1550	Radeon X1550	No
Radeon X1300 XT	Radeon X1300 XT	No
Radeon X1300 Pro Radeon X1300	Radeon X1300 Pro Radeon X1300	No

And finally the third generation, CrossFireX, is a Native CrossFire connection that allows you to connect up to four video cards based on ATI/AMD chips. The connectors and bridge are identical to Native CrossFire, the difference is how they are connected (see Figure 11). So far only Radeon HD 3870 and Radeon HD 3850 support this new mode. CrossFireX is part of AMD Spider gaming platform. Of course you will need a motherboard with three or four PCI Express x16 slots in order to use more than two video cards. It is very imoportant to notice that AMD started recently calling all generations of CrossFire technology as "CrossFireX".

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Figure 11: CrossFireX.