Neoseeker published a review of EliteGroup's 955X based PF22 Extreme board, which features Crossfire support as one of its highlights.

Along with the usual things you can expect from a i955X motherboard, Elitegroup's PF22 Extreme also supports ATI's dual-graphics "CrossFire" technology. Similar to NVIDIA's SLI, CrossFire allows users with a PCI-Express Radeon "master" card to boost 3D graphics performance by adding a second compatible ATI graphics card. The low-down on CrossFire is that both cards do their share of work to their fullest capabilities, with the secondary card sending its rendered image to the master card, where the entire image is assembled on the compositing chip before being sent to the display device.

ECS PF22 Extreme Review