I have installed Ubuntu (12.04 AND 14.04 separately, multiple times each) onto a 32Gb USB flash drive. The flash drive boots fine on a spare laptop (older HP DV7, windows 7), however on my HP DV6-6b04tx (windows 8) it hangs on an empty black screen (with back-light on) straight after my BIOS splash screen.
If I hold down the shift key on boot it gets stuck on a black screen with the text 'GRUB Loading.' and nothing else. These screens never change until I reboot. In both cases (empty black screen and loading Grub) the fan spins at max speed.
I have previously installed Ubuntu onto the internal SSD HDD and it booted fine, a live USB also boots fine. I am installing Ubuntu with a /boot partition and a separate partition for /, both ext2. I first attempted to create the root partition as encrypted however the same problem occurs with an unencrypted root partition.
I have updated the Grub config to remove quiet splash so that I would hopefully get some error output however this changed nothing (Still loads empty black screen/stuck on 'GRUB Loading.').
I found many people with similar issues on HP laptops with switchable graphics (ATI Raedon 6770m & Intel HD4000) so I followed some advice to load Grub in text mode, and to disable the ATI card (using vgaswictheroo) - again this changed nothing.
Any help would be greatly appreciated.
UPDATE: I have now also tried setting Grub config to use nomodeset and acpi_osi= , again no change