My trusty 867 15'' TiBook has been having an intermittent problem coming out of sleep. 95% of the time, it comes out of sleep just fine but every once in a while, it doesn't. You can hear the drives and fans power on but the screen stays black. Keyboard doesn't work. At that point I have to use the magic mini-button under the keyboard to reboot it. There is nothing in the logs after it boots up. It seems that the problem started with 10.4 install but that may be a coincidence. Did anyone else had this happen with their laptop?