Ok so I have a 2009 27" IMac. I already had a OEM copy of Win 7 partitioned and running perfectly fine for months. Recently I was sent a message from Apple about needed to bring comp in to get a possible faulty HD swaped out. I bought a Time Capsule first to back everything up and had the comp "fixed". Upon returning I had it reset everything back to normal. I just got around to actually needing to go into the win7 area so restarted and such. There was no longer a Windows option but a "backup" which I tried clicking on and nothing happened.
Ok I figured no biggie I will just reset everything with a reinstall. I put the Win7 disk in and started bootcamp. Bootcamp said I needed to put certain apple files somewhere so I chose my HD. I set the partition size and hit next. I was shown 4 partitions on my computer but only the last one was the size I set and was free. It also said that that same one was unable to be used as it wasn't set to FAT. WTH! Ok so I formatted that piece and then it started the install. As I've installed Windows since it came out I know it can take awhile and such. I was there and checking on everything. I finally saw it rebooting itself and then it went dark again. This time for good. I kept checking for 2 hours and nothing was going on. The comp was still on but the fan was no longer running high or giving off tons of heat like normal. I couldn't get the screen back up no matter what I did until I did a hard reboot.
I got a screen that said Win was not shutdown correctly so I tried safe mode which then gave me a cannot continue install without reboot into normal mode. Ok rebooted and went right into black screen. I went into Mac mode and deleted the partition to try again. I then restarted and setup partiton again to which I got same issue about non FAT. Re-did whole procedure again but still even after overnight wait only a black screen.