I had cause to call CenturyLink support recently. As one of the troubleshooting steps they seriously claimed that a power strip is not capeable of providing sufficient power to a DSL modem, and that it must be connected directly to the wall to receive sufficient power.

I suspect this was to force me to unplug and powercycle the modem, but I had done that several times already. The idea that a DSL modem draws more power than will flow through a power strip is ridiculous.