What the HDMI plug in do to my monitor?

Why does my Dell Studio 14 wireless internet connection stop working when I plug in an additional monitor through the HDMI out port of the laptop?

• Basically the internet cuts out as soon as I plug in my second monitor. At first I thought it might be interference from the cord, but I tried many different positions with no effect on the wireless signal. As soon as I unplug the second display the internet will come back within 30-60 seconds. It seems that somehow utilizing the video out via HDMI is interfering with the wireless network adapter. Furthermore, I used the same cord and monitor in the past without a problem (but in a different apartment), Coincidentally, the fan appears to be running more than usual on the laptop which improved when cleaned with compressed air but still has not fixed the internet problem.

• Answer:

  While I can't provide you with a definitive answer, I have some suspicions about what might be going on. The key is that you said it was working previously, but in a different apartment. I suspect there is some internal radio frequency leakage from your HDMI interface inside your device. This leakage is interfering with the Wi-Fi signal. Wi-Fi operates on several different channels, each with a different frequency. It is possible that in your old apartment the Wi-Fi used a different channel that was less susceptible to the interference. If you own and control your Wi-Fi access point (i.e. router), go into the management interface on it and select a different channel for the Wi-Fi radio. If you don't control it (it is a service provided by your apartment) then you might try looking at getting a Wi-Fi extender device (here are some on Amazon: http://amzn.to/1CAS3Ut). These devices act as repeaters, receiving your main Wi-Fi signal and providing an additional one that you connect to from your device. The repeated or extended signal will be on a different channel. You can put the extender in another room or on the other side of the room.