I had been running 10.7 since it came out without a single issue. After installing 10.8 on my 2011 MBP quad core I'm having a bad issue with it. Basically the computer will sleep and not wake. Sometimes I get a gray message saying that your computer had to be restarted for some reason. Other times I have to do a hard reset on it. It's gotten progressively worse in the last couple of days. Any idea what could be wrong or how to fix it?