I’ve been using my laptop as a USB charger for my media player (usually an iPod Touch). Each night, I play an audio-book from my media player (usually iPod Touch), which needs to be charging (via USB).
Is there an alternate OS (to Windows) or an extremely low power setting for that would allow me to use my laptop only as a power supply for my devices?
In Windows 7 there is a setting to permit USB charging during sleep and standby/hibernate: In control panel
Power Options >
Advanced Settings > (choose from dropdown) >
USB Settings, check the box
USB selective suspend setting.
If @minopret’s answer to have to laptop charge the device when in a low power state doesn’t work, then I would suggest leaving the computer at the BIOS screen. The USB ports are probably powered so keyboards would work in BIOS mode, and the hard drive will probably spin down because it is idle. I assume everything else would be minimally powered. Some laptops can heat up because the temporary sensors don’t ramp up the fans when in BIOS, but if your laptop doesn’t have that problem, then the BIOS screen may be the minimal power needed to power the USB ports with the computer on.