While away for the long holiday weekend, my UPS battery went out. I had it set to turn off the computer automatically should this happen. I assume that is what happened, although I was not there to verify. I tried to start my G4 by switching the plug to an outlet. The start button lights up as long as I hold it down but nothing else happens: no fan, no monitor display, no chimes. I've checked the cables and cords and find nothing wrong there. Any suggestions? Is it really time to upgrade? Thanks.