Close lid, open lid, get logon, logon, then screen goes blank

[BarryVG]

The ability for the system to close the lid is set to show a logon screen upon re-opening.  This happens, but the screen goes blank after logon.  No desktop appears.  This issue is on three separate systems, all running 2.6.  All updates have been run.

Sometimes requires turning off cptr, sometimes a flurry of key tapping may bring back a second logon screen. Desktop may appear but not always.  Again, settings are the default that come with the install.

Any advise greatly welcomed.