Comment 119 for bug 1309578

Also had this problem with an AMD A8-5600 and MSI A78M-E35 Motherboard. The .iso would reboot before getting to the desktop screen. Finally found a solution.
    When booting the .iso image and the keyboard icon appeared at bottom of screen, I pressed any key to enter the options menu. Selected F6 - other options and then selected acpi=off. The .iso then booted without rebooting itself before it got to the desktop, and installed OK. After 14.04 amd64 was installed, the fact that acpi was set to acpi=off in the grub.cfg file was keeping my computer from shutting down properly, so I set it back to acpi=on in the grub.cfg file. Then my shutdown worked properly.