Hi Folks,

I've been tasked with trying to implement Bootcamp on the new 3Tb hard drive iMacs that are now available. As you're all probably aware, putting Bootcamp on these computers wasn't supported by Apple until 10.8.3 comes out.

Apple had two separate issues with Windows. 1) If the Windows partition goes across the 2.2Tb mark on the HD, then Windows doesn't work. 2) Windows also doesn't work if it's placed on any partition higher than no.4.

Here's what i've found:

In their efforts to keep the Bootcamp partition as partition 4, Apple's doing some massively messed up things with CoreStorage. They've CS'd and then split the "Macintosh HD" across the hard drive while NOT adding the Bootcamp partition into the CS groups.

You end up with partitions in the following order: (i've prefixed the partitions that are part of CS with CS). (The sizes are what you get if you split the disk neatly in two, so 1.5Tb for Mac and Windows each).

0 - EFI - 209.7Mb
1 - CS Macintosh HD - 698.2Gb
2 - Recovery HD - 650Mb
3 - Bootcamp - 1.5Tb
4 - CS Macintosh HD - 801.4Gb
5 - Boot OS X - 134.2Mb

The last partition is the interesting one. I've never seen that one appear before in all my CS tinkering. It's certainly not on my other macs that I have to hand.