Thanks Countach69 - for all of your pointers. (It will take me a short Sabbatical year to follow them all through :-) >-Any specific BIOS settings related to fan speed; Always on, Only ON when reaching X degrees Celcius etc. These are preset, and beyond my reach. (fan turns on above 70 C when AC power is ON, 80 C when on batteries. So no surprises, withouth AC, the fan is on a little less.). >-Since your laptop is probably 5 years old there could be some "dust bunnies" clogging airflow Yep. Hoovered both inlet an outlets. >-Unhook any unnecessary peripherals (joystick, wireless device, ADSL modem etc.) and reboot. I have none, except 'wireless device' with is very necessary for me. It makes no difference with or/ without. (In any case Process Explorer tells me this is not taking up more than a few percent (<3%) of processor cycles.) > -Can you associate an event when this problem started occuring? This is a tough one. As you say, the laptop is >5yrs old, and a lot of s/w has come (and gone) in the meantime. I've cleaned up (registry, cache, temp files, etc) as far as possible. Defragged too. Still to try: >-Does you computer behave the same when you boot in Safe Mode? (intersting...) >-Have you tried using the Microsoft Configuration Utility (msconfig.exe) to disable programs from loading at startup? will try disabling things off one at a time... this way I know what I need, if something stops working thanks again