Hi! We have a Aluminum Powerbook about 16 months old. We often use it with an external (non-Apple) LCD monitor, via DVI. For most of the time we've had the PB, there was no problem at all. However, in the past few months a puzzling problem has developed. When the monitor is plugged into the PB's DVI port, the PB will believe there are two monitors available (the external monitor is used to provide more screen space, not to simply mirror, so both monitors are to be active at the same time), but it will not send any signal to the external monitor at first. After about 10 minutes, it will suddenly start sending a signal to the external monitor and everything is fine. However, if the PB subsequently is allowed to go into sleep mode, upon resuming it again refuses to send a signal to the external monitor for about 10 minutes. Any idea what is going on and how this might be fixed? It's really frustrating. Thanks!