>[me yesterday:]
> [..] everything works again after having redone all upgrades in
> slackware-current (remaining careful to not approach xfce desktop for the
> moment, though).
As I saw, in slackware-current one pkg for xfce has changed again, so I gave
it a try - yes, there is no surprises anymore, as I had it yesterday with
rising temperature.
Xfce looks fine now on this laptop as well.
Additionally, I took a bit more thoroughly a look with kernel 3.9.4, which
just arrived, maybe to find how to avoid that nasty erroneous CPU load.
In short: Kernel 3.9.4 is working now as well.
Found a configuration detail for to cure the problem. In ALSA sound, PCI
devices, Intel device, I just accepted the proposed ticks, for being
included, as presented by default, when entering this item newly. Before, I
had switched off in this Intel section all details in support for other
sound devices.
Bingo!
****
( Sound is working for me as well via internal card, as externally via USB.
To have cards numbered in ALSA properly, this may be configured by the names
of the cards as found by <cat /proc/asound/cards>, and the names of the
sound modules, in </etc/moprobe.d/modprobe.conf>, so e.g.:
options snd_hda_intel id=Intel index=1
options snd_usb_audio id=UA25 index=0
will introduce "UA25" as default to the machine, instead of the built-in
soundcard "Intel". This is default then for the browser and other programs,
which look for "card 0" instead of being configured via ALSA name.)