Hi there.
I have an ubuntu x64 13.04 installed on my zenbook prime ux21a laptop in EFI mode. The thing is that I got freezing right after "Loading initial ramdisk" (ctrl+alt+del / power button works though, so I don't think that counts exactly as "freezing") both in basic and recovery mode. The strangest point in all of this is that problem above is not reproducing when I'm pressing the "esc" key on boot and selecting boot device manually (or doing the same from the BIOS using "override boot device" or smth like that).

I have the latest BIOS flashed and there are all stable system updates installed. Thanks a lot in advance.