laptop fan permanently on in FC5

[Dave Mitchell]

under FC3, my laptop fan seemed to do the right thing: off or nearly off
most of the time; switching to a high speed whirh after the CPU had been
at max freq for a while.

Since installing FC5 (and putting in a higher-capacity hard disk),
the fan is contantly on at a low-ish speed regardless of CPU frequency.

Any ideas where I should look?

Its a Dell D400 with 1.4GHz Intel Centrino.

-- 
Little fly, thy summer's play my thoughtless hand
has terminated with extreme prejudice.
        (with apologies to William Blake)