Kubuntu Hangs intermittently. Video goes crazy from time to time.

[Juan Marcelo Rodríguez]

Hi guys,
Kubuntu hangs intermittently. This is awful and very uncomfortable.

Hardware: Dell Vostro 1520 - Intel dual core 2.20 Ghz - 4 Gb. RAM -
Video Intel - Broadcom WiFi.

Karmic Koala - latest version installed from daily cd version of
Karmic Koala and then updated to the latest packages.

The kernel gave the : hpet increasing min_delta_ns from time to time.
Then, by time to time I don't receive anything, but I got the video
going crazy, hanging the system.

Also I got, as a warning or error or advice, from dmesg the following :

CPUFREQ: Per core ondemand sysfs interface is deprecated - up_threshold

This is awful, absolutely awful. And makes impossible to use the
system. I tried the following kernels : 2.6.32-020632rc1-generic,
2.6.31,
2.6.31-10-generic and 2.6.30-02063006-generic.

Any ideas ?. I read that the problem is with hpet. However I have hpet
disabled in Grub2.

Thanks.

Juan