Fighting for the power.
    Hans Petter Selasky 
    hselasky at c2i.net
       
    Mon May  4 07:24:06 UTC 2009
    
    
  
> 2. PCI devices
> PCI bus provides method to control device power. For example, I have
> completely no use for my FireWire controller and most of time - EHCI USB
> controller. Disabling them allows me to save about 3W of power. To
> disable all unneeded PCI devices you should build kernel without their
> drivers and add to loader.conf:
> hw.pci.do_power_nodriver=3
> To enable devices back all you need to do is just load their drivers as
> modules.
The new USB stack should turn off USB HC's automatically when not in use. At 
least the schedules will get disabled. Did you do any research on this?
--HPS
    
    
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