When you get home tonight i suggest powering down your computer and monitor, unplug them from the wall outlets, wait a couple minutes then plug back in. Make sure all connections to the computer and monitor are secure. When your using your wireless connection plug in both the USB and the green connection. If you have a non-wireless mouse with green connection and non-wireless keyboard (purple Connection) try those also. Power up your computer first, then your monitor. Listen for any beeps also. If anything changes or if your problem still persists let us know.
I know these suggestions seem kinda obvious but ive had PC's do similiar things to me. plus it will help narrow down the cause of the problem.
P.S. if ya need help with any kind of copmuter related problem go to a forum like this or an IT friend before you go to a place like Fry's or best buy, there "IT professionals" are usually full of crap and they usually try to sell u expensive hardware/software you dont need.