I just recently purchased a Mac Pro which has the ATI X1900 card. I'm also running dual monitors and upgraded the RAM to 3Gb. Ever since loading bootcamp and xp, when in OSX the system randomly freezes (not one application causes this). I'm able to use the mouse and move it, but unable to click on any application or do a "force quit". I then have to hard shut down. Also, one thing that was odd, I'm unable to use the Alt key at bootup/restart to get the OS selection menu. I always have to go to start up disk in system preferences to swap over to Windows XP and vice versa in XP to go back to OSX. Has anyone experienced this or have ideas to troubleshoot? Thanks in advance.