Gray Screen, wont Boot

[Pili]

My powerbook (10.4.11) decided to not boot tonight after just getting my mac pro . It sits on the grey screen for about a minute with the spinning "loading" icon and then will just shut off. I booted off the install disk and tried repairing the drive and that failed which i figured but whats weird is that i can still access the data on the drive through target disk mode though there is an error that says the drive must be backed up and is under limited functionality.

Any ideas on whats going on? Thanks

 

[EricNau]

First things first, do you have an up-to-date backup? If not, get on that right now.

 

[Pili]

yes, i have everything backed up to an external.