Hi- I have a Gateway PC monitor that I have hooked up to my imac DV. About every 20 minutes or so they both shut down, no power to either one. this happened twice, the second time I was unable to turn back on my imac. I unplugged it and then it came back on. I unhooked the PC monitor and have been too afraid to use it again. I need the larger screen to edit video with. Any tips on how to get this to work? Thanks!