Is this a hardware or a software problem?

[Rivera Valdez]

Hi, is it possible to know where (or which) is the source of the problem
from this info: http://pastebin.com/yX1W6jcx ?

Those are the logs of the moment when the OS (an updated debian on
a 10 years old pc) hanged and put me out of session (I had to re-log to
my user account). This has been passing for weeks, randomly, and usually
the system hangs and doesn't respond to nothing (Ctrl+Alt+F2, etx) so
you have to reboot.

Thanks a lot!