Question Graphics card turns off and on when ethernet port is at or above 50% usage ?

Feb 10, 2021
Motherboard is Z390 Aorus Ultra BIOS-F9 (Manual) layout on Page-5
i7-9700K @ 5ghz and 32 GB RAM @ 3200 MHZ.
PSU 650W.
1TB nvme SSD in M2M.
3 HDD and 1SSD in SATA3 in ports 0,1,2,3.
Gigabyte 2060 Super in PCIEX 16.
1-GBPS TP-Link LAN adapter inserted in PCIEX1_3.

Problem: Whenever this ethernet adapter inserted in the PCIEX1_3 reaches above or near 50% usage (internet speed is around 500MBps or above, total=upload+download simultaneously on Bittorrent), problem starts. Now if I click on a video in which graphics card suddendly draws power above 50W (according to HWMonitor), graphics card turns off and after 3-5 seconds, it automatically turns on again. And now even if I run more video and even reach 180-190W power on graphics card, it remains on.

But if close the videos and GPU power goes down to normal and again run any video and suddenly if it draws power above 50W, graphics card turn off and again turn on after 3-5 seconds.

It only turns off when, after LAN adapter is 50% or above usage and the video is played for the 1st time and the power suddenly reaches above 100W. I can hear the graphics card fans turning off and on.

But when I open anything other than video, like MS Word or My Computer, the screen freezes for few second or that particular application window freezes for few seconds. And if I open Chrome Browser, grapohic card turns off and on.

I do not know what the problem is but based on some logic that it seems to be a power issue, I think that when PCIEX1_3 uses more power, the sudden requirement of a lot of power by GPU is not provided by the motherboard and it turns off and after few seconds when required power comes it turns on, in this whole process the performance of LAN adapter is not affected.

This issue is not experienced on the onboard ethernet port and only started when I attached this extra LAN adapter and only when it reaches 50% or above usage and after that if any application is opened, graphics card turns off and on. And no error comes on the screen but in the Task Manager I can see the Windows Error Reporting Tool working and AORUS Engine application closing and I have to restart that application.

Has anybody experienced this issue?
Feb 10, 2021
What is the actual make/model of your PSU? Also, why use the stand-alone network adapter at all?
Antec EA650G PRO 80 Plus Gold 650 Watt...
I have two internet lan cable connected to onboard port and other connected to LAN card.
On torrent both connection works simultaneously.