Why does my desktop seem to be effecting the internet?

[tech2]

My desktop pc is having issues when my wifi or 4g tethering are connected. They are ok for a while and then lose connection.

There dosen't seem to be any problems on other devices connecting to the modem wifi.

 

[FixitmanArizona]

You're going to have to provide more details. No one can diagnose a problem without knowing, at minimum, what hardware, what OS, etc.
Sounds like (and I could be wrong) either overheating causing something to shut down physically, or a timed disconnect.