500 gb Internal Hardisk turn 128gb

I've just installed a hard disk on my old Powermac G4 Dual 450. Turns out to only have 128 capacity when the hard disk is actually of 500 gb capacity.

I called AppleCare and they suggest that i send it down for their technician to service, for a price. Just like to try my luck here before making any money-making decisions.

This is not an issue with the HDD but with your G4, which cannot see IDE drives of greater than 137GB, giving you a 128GB partition. I cannot remember where I read this, but it's a limitation of Motherboard I believe - something to do with 28-bit controller.

I believe that Zoolook is correct. I am not sure if this will work, but you can try to making partitions of 137gb or less.