Here are notes from installing Ubuntu Linux 13.10 and 14.04.1 on a Toshiba C55-A laptop.
Computer hangs during boot (with a black screen and the backlight on)
Booting the Live DVD results in the computer freezing. Using
pci=biosirq resulted in the boot getting further along (which you can debug by also removing the
quiet options), but ultimately it was necessary to add these kernel command line parameters both when booting from the Live DVD and in