XPS 8960 won't hold an internet connection

My XPS 8960 won't hold an internet connection for more than a few minutes. The modem and the router work well for other computers and devices. Support Assist, troubleshooting, restarts, resets, clear outs, etc. also have not worked. I have the latest BIOS and reinstalled the driver. I also made sure the connections to the antenna were tight. 

The computer show that I am connected to the internet, it everything is fine for a few minutes, and then, even though it still shows that I am connected, nothing works. 

Could this be a hardware problem versus a software problem? Any additional thoughts on what I can do to identify the issue. I am getting no error messages. 

Thanks, Ann