PC cable Internet help

I have Optimum Online cable Internet, and it usually works fine, but lately I've noticed that if I've had my computer on for a while (say overnight), Web pages won't load. Logging out and back in doesn't help, but if I restart my computer, the pages load again immediately.

Obviously, that's one solution, but my old computer sometimes goes wonky during a restart, so I'd like to avoid it. Does anyone know another fix?

Have you tried just closing your web browser then reopening it? Firefox on my mac sometimes has a similar problem but if I quit and restart Firefox, it works fine (plus it asks if I want to restore the former session, so I don't have to renavigate my pages).

How are you connected to your modem? e.g. directly, or via ethernet through a router, or via wireless through a wireless router?

Have you tried resetting your connection:
run...command... then playing around with ipconfig:
ipconfig /release
ipconfig /flushdns
ipconfig /renew
There's probably also a way to deactivate and reactivate the NIC hardware for ethernet without rebooting, but it escapes me right now. Easier if you're using wireless, you can just turn off the radio and turn it on again.

Have you tried just unplugging the cable modem for a few seconds? I have Optimum too and that usually works for me if it starts acting up.

Closing and reopening my browser doesn't help, nor does logging out and back in; I have to restart my computer completely. I will try unplugging the modem tonight, and try resetting the connection if that doesn't work. Thanks for the tips everyone!