sys.Error 0x7e

Random blue screen errors 0x7e,0x5,0x0,0xf8a00a8c,0x8a00788.  I have been researching this error forever and cannot find a resolution.  The event log is of no help as well as the diagnostic results.  I've contacted dell with this issue with no satisfaction as of yet.  The error seems to occur randomly when i am away from the computer for some time.  I usually close all programs but leave the computer on.  When I come back turn on the monitor there is the blue screen.  As i have mentioned it is only random and does not happen every time i leave the computer running and come back.  I have encountered the error only once just recently while shutting down.  I have not installed any new periphs/hardware/programs.  One question though at the Ms help/support site i was instructed to check the default value for regedit.exe the DEFAULT folder said (data) value not set ---should there be a value set there?  Needless to say i was not going to try to do anything to my registry.