Default Gateway not available, disconnects every few minutes

I'm disconnecting every 30s-5minutes, and when i click on the troubleshoot problems button it says the default gateway is not available, and then it restarts the modem and it then works.
I am using comcast's default modem/router all in one combo.

I made sure my power settings weren't turning off the adapter.

I attached my ipconfig/all.

Any help is appreciated.

I'm also noticing this happens much more frequently when trying to connect to twitch.tv to watch streams or similar sites.

The problem is Comcast's so called modem/router combo units which creates this exact problem on many different machines.

If you don't want this limited connection problem then you should obtain a stand alone modem with a third party router, not one of those combo units which aren't reliable at all.