I've done a search, but couldn't find this anywhere, so here goes:
If you are the proud owner of a new'ish HP Pavilion, with a thermally controlled CPU and Case fan, you should be able to control the setup via the Advanced (uhuhhuuh secret) Bios, hit F11 during POST to enter.
In the health monitoring section, you should now have a few more options than the standard F1 Bios. You can now choose a hot and cold temp for the fans, and select what fan runs at what voltage, ranging from 5.5v to 12v.
Nothing Speedfan can't do, but if grandma' is bugging you about her noisy Pavilion, then this may help...
Managing the onboard fan control in HP Pavilion PC's
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