Bought A iBook From eBay No Admin Name Or Password

Please Help
I bought a computer from eBay that belonged to a school.
It is a iBook G4 1.33Mhz G4 512MB Ram 40GB HD running OS X 10.4.
It was sold to me with out the Admin user name or password.
I was able to login using Student, Student user name and password.
The optical drive works I checked it.
I have tried
Command S
Holding C
Command C
Command Option Shift Delete
Nothing works.
It just goes to the login screen or shuts down depending on the command you use.
I know I could get the HD replaced but it would not be worth it.

G'day and welcome to the forums.

Trust you have not purchased an eBay lemon! You need system install discs to format the drive. You can either purchase Tiger OS X.4 or Leopard OS X.5. OS X.5 Leopard is pretty dear, but make sure you get a full retail install DVD and not a silver/grey model specific disc.

Also for a modern operating system the hard drive is too small and insufficient memory. If it is a 2004 model it can handle 1.25GB ofv memory.

Trust you did not pay more than about $50.00 for it.

I have already tried this and it does not work.
I have every OS X and none of them work.
That is why I put that I used "command c" and "c" to try and boot from a cd but that does not work.

There is a way around that but it's been so long. Let me research it a few and will be back. It's C to boot from the CD. Not Command C. When you first hear the Startup sound you hold C and KEEP IT DOWN. Not Tap it. If that does not do it try the same but after the startup sound hold the OPTION KEY down and keep it down. See if you get a boot menu. BRB with the rest of the info.

Ok, here you go. Not sure which OSX is on that iBook but this covers it all. Read it all carefully and get back to us if it works!!

http://www.macyourself.com/2009/08/03/how-to-reset-your-mac-os-x-password-without-an-installer-disc/

Harry, a 1.33Ghz G4 iBook takes 1.5GB RAM. Have one here and runs 10.5 decently. I own that exact iBook. Sure it's old now but unless he paid a lot, it's ok to mess with OSX on.

Also what OSX CD or DVD are you trying to boot from? Only certain DVD's are going to boot. Nothing Intel will boot and no Gray CD/DVD will either because they are machine specific. The latest OSX that will boot and run on that machine is 10.5 Leopard. It has to be a Black DVD and not a Gray DVD that came with another Mac.

Let me take a different approach: what was your purpose in buying this 9-year-old machine?

Just a note, I put the info into Mac2Sell. They say that machine with those exact specs is worth $140!