Hi I don't know this will happen on other powerbook or just mine, or ibook..But give it a try step by step: Under fresh install tiger without 10.4.1 update: 1. unplug power supply and leave usb mouse plugged in. 2. close lid and make sure laptop enter sleep mode. 3. Double-click mouse several times. The laptop should be still in sleep mode. 4. Plug the power cord in! Now the computer should wake up with the lid closed. 5. Open the lid, see if you still got right display settings or just black screen can't see anything. ------------------------ Under latest tiger with 10.4.1 installed: Do the exact same steps above, see the result. On my powerbook, instead of getting black screen, the screen look normal. But go to display settings to see brightness bar. The knob is moved to the lowest position but the real brightness is NOT the lowest. The real value and the knob position are not same now! See if your powerbook are same as mine when doing this.