Hey, new time user here! I have an iMac 27" late 2009 and i have recently been trying to install Windows 7, but every time after a couple of restarts, i get 'cannot boot' messages, when i actually got in to Windows, everything freezes, and takes 15 mins to respond to a mouse click and all the games i run crash after 10 mins. I have tried reinstalling windows at LEAST 6 times. I recently tried to use the new Win. 8 preview but to no avail, same problems and corrupt files. I took the iMac to Apple and they ran diagnostics on the HDD and the hardware and everything is fine. Also, the mac partition works fine and has no issues. Whats going on???