UPDATE: You do NOT need that RAID controller to install Ubuntu 12.04.2. See this following link for an easy instillation of Ubuntu 12.04 onto your Dell T110II:  en.community.dell.com/.../20372542.aspx
I just purchased my second Dell Tower Server, a Power Edge T110II, and have run into a great deal of difficulty trying to install Ubuntu 12.04 as an OS. In my prior Dell Server all I had to do was to place the ISO image of Ubuntu Server into the CD and it uploaded into the Server hardware with virtually no problems what so ever. I have been searching through the manual and on the Internet to find help with this but as of yet I have found nothing that addresses this problem.I repeatedly receive error messages that the disc(which is an official Ubuntu disc) can not be booted or when I actually get as far as seeing a screen giving me the opportunity to install Ubuntu it hangs up after just a few lines of code appear. I have tried doing the instillation with both BIOS(which doesn't seem to work at all) and UEFI which gave me a screen asking if I wanted to install Ubuntu. I might add that I have not figured out how to disable the Quick Start which was suggested in a blog about installing Ubuntu using UEFI. I have searched through the forums here to find more information on how to install Ubuntu Server on a Poer Edge T110II but have not found anything of use as of yet. Any ideas would be gratefully appreciated and once I figure out how to install Ubuntu on this Dell Server I will post a blog with complete instructions on how to do it to help others avoid experiencing this SNAFU. BTW, the Power Edge T110II HAS been certified for use with Ubuntu.  See HERE! But no real documentation for this as of yet by Dell. :-(
Installing OS Ubuntu Server 12.04 onto Power Edge T110II far more difficult 
than it needs to be.