Losiing WiFi when a certain computer is connected

[TradeMark8526]

I have a recent occurance.  My wireless devices have limited or no connection to web when my main computer is on.  When I shutdown this computer, everything works great.  I suspect that this computer is hogging the bandwidth.  I ran McAfee and Malewarebytes and says it is clean.  I have not downloaded any new software onto the computer.  Everything was fine a few days ago.

I am running on Windows 8.1.  How can I look for programs running in the background or other ways to trouble shoot this?

Thanks

[Telcoguru]

You can press ctrl-alt-del at the same time and open the task manager. Now open up Networking at the top. It will show if the computer is using a connection and how much. You can also look at the processes and see what is running on the computer.

[TradeMark8526]

I did find that after my post.  I do not see anything unusual (that I know of).  I watched the Ethernet in performance, it does not seem busy (again layman's opinion).  Shows small spikes of 8 or 16 kbps but nothing constant.  I have a second computer that is hooked up by ethernet cable and that is working fine for it but my wifi connections are still not getting service.  These do see the router and are getting 3 bars but no data is getting through.

Any other ideas at what I should look for?  Is there a switch that makes ethernet preferred over wifi?  I am scrabbling for something here.

Thanks

[smith6612]

Do you have anyone else who uses this computer?

When the wireless devices report limited to no connectivity, do they still show an IP address?

Does the problem computer have a wireless card installed to it?

[TradeMark8526]

Yes.  I have 2 kids and a wife.  To my knowledge and as what I can see, no new programs were loaded.

Yes.  I see IP address on devices.

The computer does have a wireless card.  It is is not connected to wifi.  It prompts me to connect.  The ethernet network is connected.

I did go through tech support and they had me reset the modem.  That worked for a bit but now having the same issues again.

Thanks