I've been using Lion since it's launch but just lately I have noticed that my MacPro (early 2008) won't sleep. If I use the sleep option under the Apple logo the Mac Cinema Monitor dims but the MacPro itself just carries on whirring. I am aware of the energy saver option in System Prefs but this makes no difference. When the time is reached the monitor goes dim but the machine just carries on. Tried SMC reset, PRAM resets, everytime I google the problem it seems to talk about Mac Book Pro not MacPro. Any ideas..thanks.