I have a 21" Hewlitt Packard model number A4033A. Everytime I try waking my computer from sleep mode, my monitor will wake up and have all these lines running across it, and the only way I can get them to go away is if I reboot my system. For some reason it only does it when it's in sleep mode. Something about waking up from sleep mode makes the monitor flip out. Does anyone have any thoughts on why it might do this? Any thoughts would be great. Thanks!