So, for a few weeks now, my G5 has been occaisionaly and inexplicably been making the sort of clicky boopy noises that you would normally expect to hear when it's starting up, or going to sleep. Just, y'know, in the middle of completely ordinary computing, not correlated with any sort of special activity. It hadn't done that before, and I didn't know what to make of it. I usually leave my computer on for long stretches, but I put it to sleep at night. Last night, I was awoken by the fans suddenly kicking into high gear, and sounding like Apache attack helicopter. But the computer was still asleep - and wouldn't wake up! I had no choice but to hold down the power button to turn it off, and I left it off for the rest of the night. This morning, I came back and powered back up, and everything seems OK. But, how worried should I be about this sort of behavior? Anybody have any ideas what it might mean? Thanks.