The solution might've been hiding in plain sight the entire time ...

I've have cable modem service for over a year now. I've never had problems before recently. Several changes have happened to my setup, so it's hard to pinpoint where the problem is coming from.

My BIL has been trying to get his new PC working with his Charter cable for a couple days now. The cable company can see the modem just fine, and Vista says the (onboard) ethernet controller is ...