Internet dies once I plug in second monitor

[The Third Thomas]

I wasn't sure whether to post this in this subforum or the displays subforum.

 

So my internet on my PC either completely dies or slows down like crazy once I connect my second monitor. My main monitor is a 1440x2560 144hz monitor, I'm using a Displayport cable, and my second monitor is a 1080p monitor that uses a HDMI cable.

These two have worked together perfectly atleast 2 months now, since I got the 1440p new. Only since 2 days does it do this.

 

 

^Monitor connected

 

 

Monitor not connected.

 

 

It also kills my Discord and it says it can't find the server for webpages. I was lucky to even have the test with monitor connected.

[♠FlamieMeister♠]

3 minutes ago, The Third Thomas said:

I wasn't sure whether to post this in this subforum or the displays subforum.

 

So my internet on my PC either completely dies or slows down like crazy once I connect my second monitor. My main monitor is a 1440x2560 144hz monitor, I'm using a Displayport cable, and my second monitor is a 1080p monitor that uses a HDMI cable.

These two have worked together perfectly atleast 2 months now, since I got the 1440p new. Only since 2 days does it do this.

 

 

^Monitor connected

 

 

Monitor not connected.

 

 

It also kills my Discord and it says it can't find the server for webpages. I was lucky to even have the test with monitor connected.

Could be a power issue, or just a really random bug. Try resetting windows if you want.

[Mira Yurizaki]

How are you connecting to the computer to the router or modem?

 

If it's Wi-Fi and this only happens if you plug in the monitor and use it, then it's likely the monitor is causing bad interference.

[The Third Thomas]

7 minutes ago, M.Yurizaki said:

How are you connecting to the computer to the router or modem?

 

If it's Wi-Fi and this only happens if you plug in the monitor and use it, then it's likely the monitor is causing bad interference.

Yes it's on WIFI, and it only happens when I use it WITH my pc. If I connect my xbox to my second monitor this doesn't happen. It happens when I plug the HDMI in my pc.

 

Before this it worked perfectly. I'm buying LAN cables soon though, so that might help.

[The Third Thomas]

11 minutes ago, ♠FlamieMeister♠ said:

Could be a power issue, or just a really random bug. Try resetting windows if you want.

I'll reset it and see if that works

[mynameisjuan]

Wonder if you are using an HDMI cable that supports ethernet and windows thinks its a connection and uses that. In control panel under network adapters check and see what there are.

[AngryBeaver]

Do you have the option to hook the monitor up to your pc via something other than hdmi?

 

Hdmi can be used to carry video and ethernet. So if the cable is bad or has a short somewhere it could be causing issues.

 

I mean this is a pretty random issue, but I would start by using a different interface to connect the hdmi monitor by.. display port would be best.

[alexicon]

2 hours ago, M.Yurizaki said:

If it's Wi-Fi and this only happens if you plug in the monitor and use it, then it's likely the monitor is causing bad interference.

If your monitor generated that much interference through EMI you would HEAR your internet slowing down. Also you'd be dead.

[Mira Yurizaki]

3 minutes ago, alexicon said:

If your monitor generated that much interference through EMI you would HEAR your internet slowing down. Also you'd be dead.

Other wi-fi routers on the same channel and microwaves can cause enough interference on your wi-fi network such that performance degrades heavily.

 

I'm surprised we're not dead yet.

[alexicon]

15 minutes ago, M.Yurizaki said:

Other wi-fi routers on the same channel and microwaves can cause enough interference on your wi-fi network such that performance degrades heavily.

Access Point radio waves causes collisions because they live on the same wavelength, microwaves use 2.4ghz so they interfere with wireless on the same wavelength (2.4ghz and 5ghz are the two main wavelengths used in all our wireless devices). If a monitor, with no radio and no way of generating waves (beyond light), is causing interference then something is probably very bad. 

[Mira Yurizaki]

2 minutes ago, alexicon said:

If a monitor, with no radio and no way of generating waves (beyond light), is causing interference then something is probably very bad. 

Well yeah, that just means the monitor is poorly shielded around any high noise generating components. But it's not going to be generating RF noise powerful enough to kill someone.

[alexicon]

1 minute ago, M.Yurizaki said:

Well yeah, that just means the monitor is poorly shielded around any high noise generating components. But it's not going to be generating RF noise powerful enough to kill someone.

It sounds like you've changed your position here. There is no way for the monitor to be generating enough EMI to affect wifi to the extent seen in this case without also sending lightning bolts across the room. I've been facetiously trying to point out that we shouldn't be worried about EMI in regards to why this monitor is causing wifi issues for OP.

 

In all seriousness, the most likely issues that I can see would be: a grounding issue in the cabling or mobo that is sad when the monitor is plugged in, the GPU is overloading the system when it has to process all those extra pixels (this could be a power or data issue), or maybe there's something going on with the other suggestions in this thread about ethernet over HDMI causing weirdness.

 

I'm like 90% sure this is a hardware issue but we should troubleshoot this instead of speculating. You should try swapping things out starting with the easiest thing, ie, the hdmi cable. Moving to LAN is also a good idea. After that move to whatever you can RMA. Try the monitor. Try the mobo or GPU (whatever is most directly connected to the monitor).

[The Third Thomas]

6 minutes ago, alexicon said:

It sounds like you've changed your position here. There is no way for the monitor to be generating enough EMI to affect wifi to the extent seen in this case without also sending lightning bolts across the room. I've been facetiously trying to point out that we shouldn't be worried about EMI in regards to why this monitor is causing wifi issues for OP.

 

In all seriousness, the most likely issues that I can see would be: a grounding issue in the cabling or mobo that is sad when the monitor is plugged in, the GPU is overloading the system when it has to process all those extra pixels (this could be a power or data issue), or maybe there's something going on with the other suggestions in this thread about ethernet over HDMI causing weirdness.

 

I'm like 90% sure this is a hardware issue but we should troubleshoot this instead of speculating. You should try swapping things out starting with the easiest thing, ie, the hdmi cable. Moving to LAN is also a good idea. After that move to whatever you can RMA. Try the monitor. Try the mobo or GPU (whatever is most directly connected to the monitor).

OK so I swapped HDMI cables and that didn't work, but when I used a HDMI to DVI adapter and used the DVI to plug it in it caused no interference. 

 

A friend suggested that she had it as well, and that it could be an EMI leak, but I really don't know. 

 

HDMI to DVI is working for now. 

 

I'll disassemble my whole rig tomorrow and clean it out to check if that might work for my HDMI cable. 

 

Thanks for the tips! 

[alexicon]

4 minutes ago, The Third Thomas said:

OK so I swapped HDMI cables and that didn't work, but when I used a HDMI to DVI adapter and used the DVI to plug it in it caused no interference. 

 

A friend suggested that she had it as well, and that it could be an EMI leak, but I really don't know. 

 

HDMI to DVI is working for now. 

 

I'll disassemble my whole rig tomorrow and clean it out to check if that might work for my HDMI cable. 

 

Thanks for the tips! 

Sounds like might be a bad port on your computer.