Dan, you can make sure your Page file is large enough. Rt click on
MyComputer>select Prop>Advanced>Performance-Settings>Advanced>Virtual
Memory-Change. You can just set both values at 600MB.
I have always wondered about this odd XP behaviour myself and can now
confirm that the ide activity is in fact the autorun feature polling
the CD drives for media. If you follow the instructions from Microsoft
here http://support.microsoft.com/?kbid=330135 and disable autorun the
light will cease to flicker.