Hi, I went on the Apple website and was looking at the Powermac G5s and saw that it were possible to have two 400GB hard drives installed on your Powermac. What is the biggest size available at the moment on SATA? Is it 400GB? I'd like to get the most storage possible in my Powermac (ordering next week, cannot wait!) and I think 800GB from Apple looked a bit costly so I figured, I could save money by installing the hard drives myself and also get more storage (thats if there are SATA drives bigger than 400GB) .