🚀 go-pugleaf

A co-worker is experiencing a problem with her MAC II.  She powers the MAC up
in the morning and things run fine for about 1/2 hour when "blue dashes"
appear on the screen at random locations.  This happens in any application
she's using at the time.  Shortly after the blue dashes appear, the dreaded
bomb box/system restart message comes up.  Selecting restart doesn't help.  The
MAC is hung.  The MAC has been sent in for diagnostics twice now, the
first time the technicians not finding anything wrong.  Still awaiting the 
status of the second visit.  Apparently, this phenomenon will occur sooner if
the MAC is warmed up.  Unfortunately, I can't tell you much about the
environment, other than getting  confirmation of connection to the Appletalk
network during start-up, and having a PCOX 3270 emulation software/hardware.
If the MAC was here, I could have determined the OS revision, etc...

Any answers to the cause of this would be greatly appreciated.
  

Thanks in advance.