[iMac] strange screen behavior + loud fan

[Bill Planey]

Hi,

I've had my new 17" iMac G5 for about 3 weeks now... This morning to wake
the screen up (the system is set never to sleep, just the screen) I moved
the mouse.  As it often does, the screen comes on, then flickers black
again, then a few seconds later comes on for good.

This time, however, something was really wrong with the colors - it looked
like something had been posterized on a 16 color palette in photoshop.
Changing settings in the Monitors preference pane changed nothing - the
garish coloration continued through a resize in monitor depth, and through a
change in calibration choices.  I made a couple screen shots.

Even worse (but, I think, connected with this problem) was that an entire
vertical column of pixels was white.  It reminded me of the horizontal bands
that were present on Sony CRT displays (because of a wire running on the
backside of the glass), only turned 90 degrees.

I restarted, zapped PRAM, ran /sbin/fsck -f   from the command line (no
probs) and booted up again - to the problem being gone.  The fact that the
screen shots I made looked like they were made on a system that was
displaying color correctly tells me this problem was not something that came
from the OS, but was hardware in nature.

When I ran my command line thingy the fan went FULL THROTTLE - really loud.
During normal operation it is always noticeable - is this normal?

Anyone have any clues about what could be wrong with the display?

Thanks!

Bill Planey