I dual booted my HP Pavilion 15-n012tx (which was pre-installed with Windows 8 pro) to Windows 7 and Ubuntu 14.04 Trusty Tahr. Booting them was fine with no errors. Installed Windows and Ubuntu in separate partitions and updated my grub to show entries of Windows 7 and Ubuntu.
Problem: whenever I select Windows 7 entry in Grub after a shutdown, it gets stuck at a pink/violet (I don’t know the exact colour but its the grub colour in a distorted way) screen, but Windows 7 loads in the background, as I am able to hear the Windows 7 start-up sound.
The same happened while dual-booting Windows 8 and Ubuntu 14.04. I couldn't find a solution to it, so went on for Windows 7 and Ubuntu 14.04.