Open Gl - ATI Displays

I have some of the systems with G5's, and Readeons 9800 (like most of the systems), and I figure out, with the new versions, with ATI Displays configured to Catalyst, on the software Catalyst start up, stucks for a while on the OPEN GL window, then goes OK,... with I do not set up a ATI Display preference, the start up is much more faster of the Catalyst Software.
What is better, keep ATI Configured and wait little longer for the start up... Do not configure ATI Displays, get rid of ATI Displays forever (Ctalys does not used anymore or so ?) ??? The funcion I note the most diference on ATI Displays was the Vertical Sync on fast moving videos... Regards
Gian