In our initial look at Intel's Core 2 Duo and Core 2 Extreme (Conroe) processors and their compatible chipsets, we mentioned that the P965 was not likely to support ATI's CrossFire multi-GPU technology because the chipset does not have the same PCI Express lane configuration as the 975X. Whereas the 975X can be configured in an 8x / 8x PEG lane configuration, the P965 is setup for 16x / 4x operation. But yesterday news hit the web that MSI had added CrossFire support to their P965 Platinum motherboard, and we have just received word from Asus that they have a new BIOS that enables CrossFire support on their P965 based P5B Deluxe motherboard. P5B BIOS rev.0706 (or newer) should be available on Asus' site in the next few days. You'll need that and the latest set of Catalyst drivers to be in business. For now though, it's looking like only X1900 CrossFire in Direct3D is supported. OpenGL support should come before the end of the year.
On a side note, Asus also sent word of a new BIOS (v1405) for the 975X Express-based P5W DH Deluxe that unlocks lower multipliers on Core 2 Duo processors, for more flexible overclocking. This feature had already been implemented on their P5B, but it is new to the P5W.