Trouble Getting New pages to load

Not absolutely sure of "Model " listed above. It's an approved unit by Comcast, I have internet only service with them, and a "business account" my upload speeds and download speeds are acceptable, not FABULOUS but O.K. Lately I'm having problems with my pc loading new/add'nal pages, sometimes just one, after starting Chrome which I use almost exclusively. I'll type in an address or copy+paste one, and sometimes just clicking on a link from another page. Often - like several times per day lately - I'll get a "Cannot connect - time out" error. Comcast, BTW, says "It ain't us!" Nothing in the house/office has changed, no new implements, nothing moved, etc. Currently the modem/router handles : 2 pc's; one TV; one Ooma phone unit; one cell-to-handheld phone device, and the occasional outbound cell calls that either of us makes.

I have no warranty left, and don't want to buy a new modem if that's not the problem. 

Should I download new/add'nal firmware? or will that potentially snafu me? you can email me directly at  :  toboro49@comcast.net

Thanx.

Tony B.