One of my Macs is an older Power Mac G5 w/ a Power PC 970 2.2 CPU. I am currently running 10.4.11 and want to upgrade the OS. When I purchased this computer, Apple didn't have a hard drive the size I ordered, so they put in a bigger one and partitioned it, only giving me access to the amount of space I ordered. This partition will not allow me to upgrade the OS. Can I remove the partition and get access to the entire drive and then upgrade the OS? If so, do I need to clone my drive onto an external drive and then remove the partition? Thanks for any suggestions.