GforgeXr :
hang-the-9 :
I work on those models a lot, but don't remember ever having to look at one for none of the status lights working, I doubt there is a bad fuse though, have not run across a removable fuse on the motherboard yet.
What is the symptoms of a bad fuse and how do they happen?
Well a fuse protects from power surges, it breaks the connection before electricity can get to the other parts. So symptom would be something not working, usually a device won't power on. How they happen, fuses actually do what they are meant to do or fail like any other electrical component. You can find tons of info on fuses in any book on electrical systems or online.