From time to time my console locks, mostly when I have left it unattended for 15-30 minutes. I can go weeks without experiencing a lockup, but eventually one will occur. I try Ctl-Alt-Esc, and also Ctl-Alt-F1 to see if I can shut down the offending application and exit gracefully. Almost never do these work, so I have to power off and reboot. Mostly at the time I will be running Konqueror, Kedit (maybe 2 instances), Kmail, Mozilla, and some application software (ciao etc).
I run Red Hat 7.1 as this is tested with my applications, and so I have not upgraded (Konqueror version is 2.1.1).
Any suggestions welcome
Greg