Fans and laptops
echo 30 > /proc/acpi/thermal_zone/THRM/polling_frequency
exit
Entering the code above in a terminal window under root sorted the fan problem on my little L400.
Previously, the kernel was not reading the temperature at regular intervals and so simply stuck to the fan state that applied when I booted into Ubuntu. Boot from cold, the fans were off and stayed off – very hot laptop after an hour or so. Boot from warm (re-boot from Ubuntu or Windows) the fans went on but stayed on.
I posted a question under Hoary Laptop Support on the Ubuntu forum and pestilence4hr posted back with his/her experience with a Gateway laptop. I think I posted enough information so that people could recognise the problem – vague posts don’t always get answers.
Support forums and OpenSource go together, no ‘smooth’ interfaces where the fans ‘just come on’ but someone somewhere may have seen the same problem and solved it. You save your disposable income and take your chances I suppose – I now have a secure virus free operating system that I can surf the Web with on this old laptop. For hacking out handouts Windows ME and Office ‘97 work fine and fast – I’m just not putting them near the Internet.