I have a very annoying problem with dual hard disk. I've got 512GB SSD and one 750GB HDD (that came with the laptop 2 years ago). I've recently tried to do a dual hard disk setup as I decided I no longer needed the DVD drive except so rarely that having it as a USB peripheral would do just fine. On the one hand, my MBP can't figure out how to power manage whichever disk is in the DVD bay. If the harddrive is in there, it's spun up 24/7 whether I need it to or not, and it's quite noisy to be honest but also drains a significant amount of battery life because it's a constantly spinning harddrive. Generally, it costs me about 20% of my battery life over a full cycle. So I tried swapping them. Clearly, the SSD will use less battery from being on all the time so that's better. But I still want my OS on the SSD. So that means my primary disk needs to be the one inside the caddy. I can't do that. If I try to install OS X on the disk while it's in the DVD bay, I will end up with the forbidden sign when I try to boot from it. However, even more funny, I can install it on the DVD bay disk, then swap the disks around, then boot from it perfectly fine when it's back "where it belongs". I can use the DVD bay disk for file storage, though. That's not a problem. Can anybody tell me how to do one of two things: Either make the disk in the DVD bay actually be power managed OR allow me to boot from the disk in the DVD bay Thanks!