I've installed 14.04 (from 11.10), it worked first, than I tried to install the 64-bit-version, which doesn't seem to be able to boot because of my old BIOS, which does not allow "efi" boot. Now I reinstalled 14.04 32 bit, but still get a grub rescue prompt when trying to boot. Running boot-repair from live ubuntu didn't help. So here's the report boot-repair made: http://paste.ubuntu.com/7410732
Hope someone can help me ...