So I've finally decided on a 2.93 quad core Mac Pro and I have a couple of questions that I was hoping the more experienced could help me out with. Hard Drives 1. For the hard drive that is going to come with the computer, is $90 a decent upgrade price to go from 640GB to 1TB? While I know I can get 1 TB hard drives cheaper, I just feel like I will replace a 640GB hard drive to a TB anyways and $90 for a hard drive I will keep instead of the $180 that is built in which I will not use seems like the smart move. 2. I understand that keeping the OS on a faster hard drive will offer fairly significant performance boosts. Most of the 10000 rpm drives I have seen are about 150 GB or less, (like this western digital) and I want to install OS X and XP. It seems like splitting a drive this small to 75/75 GB leaves me with way to little space, even when storing most of my files on a different hard drive. Is it possible to have the OS on two separate hard drives, or do they both need to be on one? I really wouldn't mind just using two 10000 rpm drives if it gives me the extra space I need. Ram 1. I definitely don't feel the need for 4x4gb ram sticks, so I will probably just go with either 3x2gb or 4x2gb sticks. I've tried looking over the posts here, as well as the linked articles to places like Barefeats, but I am lost on why you would not want to fill all the ram slots... just confusing me. Sorry if the post is a bit long or dense, but hopefully someone can muddle through it.