Ethernet Issues with Strix X570-E Board

[dertom]

I'm at the end of my wits now, so I'm open to any suggestions.
Starting position:

Ryzen 5900x
on said board
32 gigs
900W power supply

Fiber optic connection with 2 gig up/down

Private PC is connected to the network by cable
Work laptop is connected to the network via WIFI

What's happening since last week:
The PC that is connected to the LAN can no longer get a clean connection.
Symptoms:

Speed ​​test (tried various): 1 gig down / 0 up (upload test aborts)
Login to various sites no longer works, i.e. I can browse a shop or forum, but when I log in it fails miserably (https issue?)
Gaming is no longer feasible (battle.net can't get a clean connect, in the game I'm kicked out after 2-3 minutes (connection to the server lost)
Even the Google search needs several refreshes before the jump to the result works

What I've tried so far:

Fiber Box:
Restart, back to factory settings -> no effect
Attached the work laptop to the router via cable -> works just fine. but its my work laptop so its connected via VPN.
Fiber Box is probably OK?

I have two Ethernet options on the board (Intel I211 Gigabit and Realtek PCIe 2.5gbE Family)
Tried it on both connections -> same symptoms

Then tested the usual cmd commands:

flushdns / registerdns / release / renew -> no effect

Of course, all drivers are brought up to date -> nothing

Then, as a counter-test, connect the PC via WIFI stick: works great. no problem

Also tried another Lan cable: no improvement

Optimistic as I was, I completely reinstalled Windows 10 yesterday -> doesn't help.

Made an Ubuntu USB Stick : same effects on linux

so I accepted my faith that both onboard adapters are broken. Though luck..
Next day I bought a new Intel Ethernet Adapter (PCIe), was all hopefull ..
guess what? still the same symptoms.

I didnt make any hardware changes prior to this glorious riddle..

Questions i've got so far:

Did I miss something?
Is it possible that the whole board is broken regarding ethernet connections?
Even with a new added adapter?

Thanks guys for reading. Whoever figures it out gets a cookie 🙂

[ationfictons]

I might have missed it in your writeup, but do you have anything else on your local network (for instance, a NAS or another computer)? Can you transfer files back and forth between those devices (if they exist)?

[dertom]

ationfictons wrote:
I might have missed it in your writeup, but do you have anything else on your local network (for instance, a NAS or another computer)? Can you transfer files back and forth between those devices (if they exist)?

well kind of.. ive got a plex server running on my pc and it streams to my tv in the living room. This feature died as well via ethernet and works again via WIFI Stick.
But its hard to tell if its a LAN issue or that the plex server needs a online connections as well to be fully working.
if I install a speedtest on my appleTV box in the living room the speeds are allright and the TV with netflix and stuff works just fine.

[ShyGuy2]

I am having the SAME EXACT ISSUE!

Have spent a few days rolling back the Realtek NIC and Intel NIC drivers and tried different variations with no luck!

Onboard Intel WIFI works flawlessly but I want the NIC's to work!

here are my drivers' versions and windows version

[ShyGuy2]

Still doesn't work

[ShyGuy2]

Will updating the Chipset drivers work??


NOPE!

[ShyGuy2]

No matter what I do the NIC's are not working correctly.

[ShyGuy2]

packet Loss on Internal Wifi



Packet Loss on onboard NIC's (Doesn't matter which one as they both do the same)