There are brand spanking new ATi Catalyst 6.11 drivers out today. The latest Catalyst drivers offer performance enhancements and fixes but the real news is the software CrossFire support for any combination of ATI Radeon X1900 and ATI Radeon X1950 running Windows XP.
Catalyst 6.11 introduces software CrossFire? support for any combination of ATI Radeon X1900 and ATI Radeon X1950 installed in a system running either Windows XP or Windows XP Professional x64 Edition operating system. Note: The ATI Radeon X1950 PRO is not supported in software Crossfire mode and can only be used with another ATI Radeon X1950 PRO in Hardware Crossfire mode