PB Issues

I have been having some issues with my PB recently. Some times when I wake it up I wont be able to use my USB mouse or keyboard, I have to restart it in order for it to work. This has happened several times over the past week. It happened today and when I turned on my PowerBook it said that my date was set to a date prior to 2001, and it told me to set it manually. When I checked the date it was correct.

I have repaired permissons thinking this was a problem, I also downloaded and ran System Optimizer X. Is there anything else I can do? The only recent changes that I have made to the PB is that I installed iLife '06 and added a 1GB stick of Kingston RAM, both of the 1GB sticks in my PB are Kingston.