Hello, I have Mac mini which had Mac OS X 10.4 operating system on it. The Mac mini used to work fine with it. I recently updated the operating system on the Mac mini to Mac OS X Snow Leopard. After updating the operating system on Mac Mini I am facing a major issue. Once it is put in sleep mode Mac Mini does not come out of sleep mode after the operating system upgrade. Can operating system upgrade create such problem? If anybody is facing similar problem then please share some information about the same. Thanks in Advance.