System doesn't shut down properly under Fedora-18

[Jonathan Ryshpan]

Recently installed F-18 system doesn't shut down properly.  The symptoms
are:

      * I click Shut Down, using KDE
      * System appears to stop normally: fan stops, screen goes blank,
        etc.  EXCEPT that the light around the power switch doesn't go
        completely dark; it continues to glow faintly blue.  I don't
        know what this means; no documentation.
      * The system won't restart till it is reset.  This can be done
        either by pressing Reset on the computer or by powering the
        system down and then powering it up.
      * When the system is restarted, a message from  systemd-fsck
        appears to indicate that the disk drives were not closed
        cleanly.  /var/log/boot.log is attached.

Apart from this, the system runs fine.

Motherboard is ASUS M3A78-EM with a 4-core CPU.