Yes. As long as electronics are kept cool, they can run a long long time. Some of the newer modems even de-power their ports to save energy, so at night when you're not accessing the LAN ports, the modem is basically just idling and not dissipating much power. Not sure if yours has the energy saver stuff in it, but even if it doesn't, during long periods of doing little work, the thing will have no problem running all night, as long as it's in an area that allows what little heat they generate to rise above it and away from it. As long as there's reasonable air space around it and the air isn't hot, those things should last.