Bootcamp Black Screen iMac 27" (Late 2012) GTX 680 Drivers?

This is easy, same problem for everyone.

Using bootcamp to install windows 7 from an .iso in a USB (just because there is no DVD drive anymore on the iMac), after restart the imac a black screen come up and nothing happen.

I think this is because the drivers for the GTX 680 MX 2GB is missing on the USB.

Where to get them and how to fix this problem?

the solution that apple has right here http://support.apple.com/kb/TS3173 it doesn't work at all, just because the driver that you download from there is for an ATI Graphic card.

How to fix this please.

I bought this very expensive imac because it is so powerfull and I want to use designing software with windows and use at the same time mac OS.

Please don't tell me about Parallels or VMware xD.

Thanks a lot

Regards