Sorry, I was using keywords and not being clear.
On my 2011 Mac Pro with Mtn Lion, new 5770 video card, and new SSD, I still have an old problem with this machine alone. Other 5 Macs not problem. Fresh install of Mtn Lion.
If I do not designate "sleep" at end of session, the machine will sleep by itself eventually, but leave a black screen that will not wake normally. Without mouse movement, screen stays black. Moving mouse "wipes" the screeen clean and I can wipe my way to the PW login box. Why only this machine?
I have a variation on this issue.
We have been rolling out Lion and came accross this issue and applied the fix suggested and it works. However the new twist is that when the user logs in all their apps have shutdown (without savaing).
For security reasons our company insists that all workstations (Mac or Windows) implement account lock down after 15 mins on inactivity. So I need to find a fix for this.