Wi-Fi issues after upgrading GPU/Monitors

Highguy · June 22

Hi all!

I’m dealing with a frustrating issue and would appreciate any advice.

Setup:

CPU: Intel Core i7-12700K
CPU Cooler: Noctua NH-D15 chromax.black
Motherboard: MSI MAG Z790 TOMAHAWK WIFI DDR4 ATX LGA1700 (BIOS 7D91v1H)
Memory: G.Skill Ripjaws V 64 GB (2 x 32 GB) DDR4-3600 CL18
GPU: Gigabyte GAMING OC GeForce RTX 4080 SUPER 16 GB (Used to have ASUS STRIX 1080)
PSU: SeaSonic FOCUS GX 850W 80+ Gold Fully Modular
Monitors (x3): Dell G2724D 27" 2560 x 1440 running @ 165 Hz (using the DisplayPort cables provided by Dell)
Router (Mikrotik heX PoE) & access point (EAP 650) are in the same room as the PC and nothing is blocking the antennas (properly screwed in as well), also all other devices are getting full speed without hiccups
Windows 11 10.0.26100,
Network adapter: Wi-Fi 6 AX201 version 23.140.0.3 & Bluetooth version 23.40.0.2
GPU running version 576.80

Issue:

When all three monitors are plugged in (all DisplayPort), my Wi-Fi barely detects 5GHz band and when it does, I can't even connect to it (either it disappears or connected without internet). As for 2.4GHz, it detects it and I can sometimes connect to it, but it is so slow that it is unusable (0.xx mbps instead of the 120mbps I am paying for). Bluetooth works just fine
If I unplug one monitor cable (so only two monitors active) OR if I drop refresh rate from 165hz to 60hz, Wi-Fi "works", as in I get the 120mbps, but there's hiccups here and there, it isn't 100% stable, but it works and reaches the expected speed. I also notice decreasing the resolution helps detecting the Wi-Fi signal as well as touching the antennas
I’ve tried an external Wi-Fi adapter (TP-Link Wi-Fi 6E AXE5400), but same issue
BIOS, GPU drivers, Windows 11, Chipset, and all system drivers (including Bluetooth & WiFi) are fully updated (also tried re-installed Windows as well), cleared CMOS as well and tried different power outlets
Previously, I had a GTX 1080 with 3x 1080p 60Hz Acer monitors and never had this issue. This issue started happening after upgrading to my 4080 SUPER and switching to 3x 1440p 165hz Dell monitors

Questions:

Could Dell’s DisplayPort or the GPU cause EMI interference?
Considering buying higher-quality DisplayPort 2.1 shielded cables, is it worth it?
PSU wattage is 850W, so I guess it is not a power shortage issue?
Has anyone experienced Wi-Fi issues when using multiple high-res monitors/DisplayPort?

If anybody has any recommendations for troubleshooting or fixes, do let me know, I am a bit at my wits end and having to always use an Ethernet cable is a bit troublesome.

Thanks in advance!

KidKid · June 22

45 minutes ago, Highguy said:

Hi all!

I’m dealing with a frustrating issue and would appreciate any advice.

Setup:

CPU: Intel Core i7-12700K

CPU Cooler: Noctua NH-D15 chromax.black

Motherboard: MSI MAG Z790 TOMAHAWK WIFI DDR4 ATX LGA1700 (BIOS 7D91v1H)

Memory: G.Skill Ripjaws V 64 GB (2 x 32 GB) DDR4-3600 CL18

GPU: Gigabyte GAMING OC GeForce RTX 4080 SUPER 16 GB (Used to have ASUS STRIX 1080)

PSU: SeaSonic FOCUS GX 850W 80+ Gold Fully Modular

Monitors (x3): Dell G2724D 27" 2560 x 1440 running @ 165 Hz (using the DisplayPort cables provided by Dell)

Router (Mikrotik heX PoE) & access point (EAP 650) are in the same room as the PC and nothing is blocking the antennas (properly screwed in as well), also all other devices are getting full speed without hiccups

Windows 11 10.0.26100,

Network adapter: Wi-Fi 6 AX201 version 23.140.0.3 & Bluetooth version 23.40.0.2

GPU running version 576.80

Issue:

When all three monitors are plugged in (all DisplayPort), my Wi-Fi barely detects 5GHz band and when it does, I can't even connect to it (either it disappears or connected without internet). As for 2.4GHz, it detects it and I can sometimes connect to it, but it is so slow that it is unusable (0.xx mbps instead of the 120mbps I am paying for). Bluetooth works just fine

If I unplug one monitor cable (so only two monitors active) OR if I drop refresh rate from 165hz to 60hz, Wi-Fi "works", as in I get the 120mbps, but there's hiccups here and there, it isn't 100% stable, but it works and reaches the expected speed. I also notice decreasing the resolution helps detecting the Wi-Fi signal as well as touching the antennas

I’ve tried an external Wi-Fi adapter (TP-Link Wi-Fi 6E AXE5400), but same issue

BIOS, GPU drivers, Windows 11, Chipset, and all system drivers (including Bluetooth & WiFi) are fully updated (also tried re-installed Windows as well), cleared CMOS as well and tried different power outlets

Previously, I had a GTX 1080 with 3x 1080p 60Hz Acer monitors and never had this issue. This issue started happening after upgrading to my 4080 SUPER and switching to 3x 1440p 165hz Dell monitors

Questions:

Could Dell’s DisplayPort or the GPU cause EMI interference?

Considering buying higher-quality DisplayPort 2.1 shielded cables, is it worth it?

PSU wattage is 850W, so I guess it is not a power shortage issue?

Has anyone experienced Wi-Fi issues when using multiple high-res monitors/DisplayPort?

If anybody has any recommendations for troubleshooting or fixes, do let me know, I am a bit at my wits end and having to always use an Ethernet cable is a bit troublesome.

Thanks in advance!

It sounds like a motherboard bandwidth issue, but you have a high end one, so that shouldn't happen. Try HDMI instead maybe, or get an external USB/PCIE Wifi adapter, that's going to be the easiest solution.