I came home today, and found my 2008 24" iMac with a white screen, and making a loud beeping sound. When I left it last night I put it to sleep, it was running just fine. I pressed the power switch and turned it off, waited a few minutes, turned it back on. It made the regular start up boing, and immediately started beeping, displaying a white screen. I've disconnected all USB/FireWire hard drives etc., restarted, with the same results. Does anyone have any idea what's going on?
Please any thoughts will be appreciated.