Hi guys, I have a Mac Pro Early 2008 3,1 and I recently buy a GTX 680. I have plug 2x24" 1080p monitors and 1x40" 4K monitor on it. That's working pretty great, but since 2 weeks there is a high-pitched sound that came from the power supply. The computer is still working great, but the sound is really annoying. Maybe 3 monitors are take too much power from the original power supply and I need to replace it ? If so, is there a compatible power supply that can deliver more power that you can suggest to me ? Thanks a lot !