I've managed to install Ubuntu (dualboot) on a HP Z1 after a few unsuccessful tries with the normal install procedure (Ubuntu 12.04). I also got a black screen after install and after lots of searching on forums, I concluded the UEFI BIOS was part of the problem.
As a mac computer also uses UEFI/EFI, I thought the solution may be to use an Ubuntu distro iso especially made for the Mac. I installed Ubuntu on a separate 2nd SSD just to keep it separated from Windows 7. My purpose is to have a dualboot system (Windows 7 and Ubuntu).
This is what I did (july 2012) in short:
- copy the ubuntu mac iso on an usb stick (there are lots of manuals how to do that)
- boot up with this stick and install normally, just select the right partition and/or disk, otherwise your Windows 7 install will be overwritten. In my case I selected to have Ubuntu installed on the 2nd SSD.
- after ubuntu is fully installed, reboot and Windows 7 boots up
- Download EasyBCD (http://neosmart.net/EasyBCD/) to alter the bootmanager. Here you have to assign the right OS to the right partition, so you can select Ubuntu or Windows to point at at boot time.
PS in the meantime, take a look at https://help.ubuntu.com/community/UEFI. It's a recently written useful article how to install Ubuntu on UEFI computers.