I have a cable connection. Recently I have been losing internet connection. Typically 1-3 minutes. ISP has checked the lines and signal strength was good. Of course my connection was fine while the tech was here.

Does this problem sound like a modem issue? It's a Webstar (by Scientific-Atlantic) and only three years old. If not what else could I check?

I will have to buy a replacement modem so I prefer to eliminate other causes first. If this sounds like a modem issue, any recommendations on brands.

Computer is an HP media center.

Hey there

Does the Modem loose connection or the PC.

Try updating the modem's firmware. Go to Manufacturer's website.
Should be under Support/Downloads

Cheers
Grant