This morning I heard my iMac g5 isight fans start going at full speed. I look at the screen and there is text on the screen. Ok I know what that is its a kenal panic. So I restart. Nothing, Restart again, nothing. Finally it starts up but now I have no power to my USB keyboard or USB mouse. I cannot press any keys to boot into anyother mode like firewire, or boot from CD, or hold the option key to book from another drive. HELP Please.