If you have EFI hardware, it is documented in the Quantal release notes[0] that it should be booted in legacy BIOS mode. It looks like this is still the case with Raring as well.
[0] https://wiki.ubuntu.com/QuantalQuetzal/ReleaseNotes/UbuntuDesktop
If you have EFI hardware, it is documented in the Quantal release notes[0] that it should be booted in legacy BIOS mode. It looks like this is still the case with Raring as well.
[0] https:/ /wiki.ubuntu. com/QuantalQuet zal/ReleaseNote s/UbuntuDesktop