Hi people, my desktop runs Linux Mint 17 as the only OS with no bootloader, but as my college uses Windows software not compatible with WINE, I need to install Windows on it (Not to mention Shadows of Mordor is coming out soon, but thats another story). I only have the one hard drive (which, I made sure, has ample space for both OSes), and I'm not quite sure how to install GRUB at this stage, since on all my previous machines with bootloaders I installed it alongside the OS. Can anyone offer some assistance?

Addendum: On further thought I may already have GRUB installed, but dont remember adding it. When I boot my computer, it goes straight into the OS without prompting me to select a system. How might I check whether its there, and if it is enable the list?