I have a G5 PPC TOWER and I am finding that the available space on the drive is inexplicably disappearing. I just thought the drive was so full (had only 1-2GB available) that the descent to zero bytes available was due to programs usage and disk fragmentation. So I installed a new internal and moved 50gb to the new drive. However the next day, the space went from 50GB to 14GB. What's going on?