Cat4.10_m119_UB_HD is crashing with Mac OS 10.4.11 and Quicktime 7.5. The machines are Mac Pro Dual Core Xeon 2.66 GHz with 2 GB RAM, ATI Radeon X1900XT video cards.
The graphics cards have the recent update, and the macs have the firmware updates.
The machines pass Apple Hardware Testing - 24 loops no problems.
The same problem is happening on both machines.

The problem is that randomly Catalyst and the entire Mac with just freeze. This can show up any from 2 minutes after launch to 2 hours after. It happens whether or not I have it attached to Artnet. Just sitting in my office with no console it still crashes. It takes a power off/on to get the Mac moving again.

Does anybody have any experience with these kinds of problems?

What do I do now?

Thanks for your help.

Michael