The machine is a new Intel Core i7 4770 on an Intel DH87MC motherboard, dual-boot (in straightforward legacy mode, not UEFI) running 64-bit Win 7 or openSUSE 12.3 with KDESC 4.10.5. Both installations are fully updated; in the case of openSUSE from stable repositories only.
There’s a problem with shutdown in oS 12.3. Telling the machine to shutdown and poweroff invariably causes shutdown and reboot instead, which I then have to intercept by holding in the physical “Off” button. This occurs whether shutdown is invoked from the KDE graphical interface or the commandline.
There’s nothing in the BIOS settings to suggest why. In any case the machine shuts down properly from the Win 7 installation, so it can’t be a BIOS thing but must be something to do with the oS 12.3 installation specifically.
I’ve experimented with the -h, -H and -P parameters, the “halt” variations, and the alternative “systemctl poweroff” command, all without success. I’ve googled all over the place, but have found nothing relevant. Intuition suggests it’s probably something in systemd, but that’s a guess – and even if it’s an accurate one I don’t know the answer.
It should be simple, but I’ve run out of ideas. Anyone??? Please!