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I installed Ubuntu 12.04 on my partitioned hard disc:
/dev/sda /dev/sda1 ntfs Windows /dev/sda2 ntfs Backup Disk /dev/sda3 ext4 Ubuntu 12.04
I can boot from Ubuntu and Windows via Grub. Now, I decided to remove the Ubuntu since I'm always stuck with getting the driver to work properly on my Radeon HD 7770 (always causing boot failure). I cannot find ways to uninstall it (there is an option in the installer where Remove Ubuntu 12.04 and reinstall it but that does suits), so I decided to delete the Ubuntu partition in
/dev/sda3 thinking it would solve the problem.
However, when I restarted my desktop the GRUB (purple background) still shows the Ubuntu, Memory Test, Windows (loader). I want to remove this so that my desktop will boot directly from Windows.