previously, the crossfire choice was 975x (maybe a couple of the ati based boards, though havent heard a peep from em since core 2). crossfire is now supported on 965 for the x1900 series in direct x, open gl by year's end.
click on radeon\catalyst driver download\release notesthen "new features"
This release of Catalyst® introduces CrossFire™ support for the Intel 965 Chipset. This feature is available for D3D applications, and is supported on ATI Radeon® X1900 CrossFire™ edition products. This feature is supported under the Windows XP operating system.
edit - ati uses session info for access to notes... kinda stupid to prevent linking to them