I updated Spybot S&D this date and then ran a scan.
Here is the log entry:
Smitfraud-C.: Autorun settings (Matrox Powerdesk) (Registry value, nothing done)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\Matrox Powerdesk
Note that Matrox Powerdesk is part of the Matrox driver package for my Matrox Millennium G450 AGP Graphics card.
This would have been a false positive run amok if I had let Spybot "fix" the problem!