DO you have Roxio/Adaptec AND Nero CD/RW software installed?

A PSU Fault Could cause this symptom... (but only if the system was at PSU max all the time.. and the CDRW drive spinning up is the straw, for the camels back).. if there are no other symptoms..
check the IDE cable for nicks or crushes or daggy IDC plug job's or daggy cable cut..

Or have you just rubbed a black cat the wrong way..

Cheers