I have a Dell U2412M monitor connected through a mini-DP to Displayport video cable to my brand new Mac Mini I bought last week (2012 base model). I use the Mini in conjunction with a Windows 7 PC through Synergy. My keyboard and mouse is plugged into Synergy on the PC and the Mac is the client. When I don't use the Mini it is set to sleep the screen but NEVER sleep the system. When the screen goes to sleep, I can not wake it up. I can press the cables on Synergy (move the mouse to that screen) and hear OS X noises, etc. but the only way to bring the display back is to press the power button twice on the Mini. Has anyone else had this problem?