Question Lost my ethernet port on Msi B550 Mortar Wifi

[Kiscvik]

1) b550 Msi Mortar Wifi
I recently bought a new motherboard, CPU and RAM to upgrade my computer (received it on the 25 of August). Installation was a success and everything worked well, until yesterday (2nd September).
I just have a lot of problems with my ssd m.2 windows partition and it just dont boot, i was using a really old version of windows and after i upgrade it i just get that problem off (windows manager i think)
When I wake up today, i just start downloads some games an then the ethernet port's LED's stopped working and it didn't show at all in the device manager. It changes to Wifi connection.

To give a bit of context, the specs of the system are as follows:

Motherboard: Msi B550 Mortar Wifi (still under warranty)
CPU: Ryzen 9 3900x (still under warranty)
RAM: 2x Corsair Lpx 3600 mhz 8gb (still under warranty)
GPU: Gigabyte 1030 (Waiting to get a new Rtx3080)
PSU wattage: 850W Xpg Reactor gold
3 fans
Chassis: Aerocool Klaw
OS: Windows 10 Pro

The motherboard in question uses the Realtek® RTL8125B Lan
Things I have tried to do to fix the issue:

1. Restart (first and foremost)
2. Update / reinstall drivers
3. Reset BIOS /update it to Last official version
4. Reset CMOS
5. Take MOBO battery out for a while
6. Take RAM out for more than 2 hours
7. Remove all fans (except CPU fan)
8. Check network cables
9. Try a different OS

None of these solutions worked. The LAN port remains 'dead' and can't be found in the device manager.

Pd: I have a Giga-usb so i test the ethernet cable on same computer and it woks perfectly. I just have this problme 1 DAY USAGE!! so what should i do, was looking all day and nothing

Pd2: Im using a nvme 1tb Sata and 2tb hdd on sata 4. (If you need more information just ask me)

Thanks.

 

[drea.drechsler]

...
Pd: I have a Giga-usb so i test the ethernet cable on same computer and it woks perfectly. I just have this problme 1 DAY USAGE!! so what should i do, was looking all day and nothing
...

I'm confused about whether you did a CLEAN install of Windows or not. If you didn't, that's the first thing to do. CLEAN install means let the install process reformat the system drive. Backup data on the system drive, and I take data drive(s) out of the system just so there is no chance for confusion.

If you did then it sounds like the NIC toasted; infant mortality. Things like that aren't uncommon with new electronics.

So as I see it you've two options. One is install a PCIe NIC in one of the open slots. But that's not cool for a brand new board that's under warranty...

So next option is take the board back to the place you bought it and exchange it. Or a sub option is call msi tech support and get an RMA

 

[mrb00ce]

If you did a clean install of windows then you have install your ethernet drivers for the internet to work

 

[Kiscvik]

If you did a clean install of windows then you have install your ethernet drivers for the internet to work

I cant because windows dont detect ethernet port, and ethernet port dont have even lights showings its working...

 

[Kiscvik]

I'm confused about whether you did a CLEAN install of Windows or not. If you didn't, that's the first thing to do. CLEAN install means let the install process reformat the system drive. Backup data on the system drive, and I take data drive(s) out of the system just so there is no chance for confusion.

If you did then it sounds like the NIC toasted; infant mortality. Things like that aren't uncommon with new electronics.

So as I see it you've two options. One is install a PCIe NIC in one of the open slots. But that's not cool for a brand new board that's under warranty...

So next option is take the board back to the place you bought it and exchange it. Or a sub option is call msi tech support and get an RMA

Hi, i just reinstall windows on main partition of my m.2, do you mean i need to use the msi tool (Safe format ) to format my m.2? if yes, i will try it now, I just take the option of install my windows on system but didnt clean the other partitions. Thanks

 

[drea.drechsler]

Hi, i just reinstall windows on main partition of my m.2, do you mean i need to use the msi tool (Safe format ) to format my m.2? if yes, i will try it now, I just take the option of install my windows on system but didnt clean the other partitions. Thanks

Do a CLEAN install using only Microsoft's installer:

https://support.microsoft.com/en-us/help/4000735/windows-10-reinstall

Don't use any 2nd or 3rd party utilities, only the Windows installer. The windows installation process will DELETE all old partitions and re-partition the hard drive as it needs to be. So you have to back up data you want saved. You should do this for a new system (motherboard) as a matter of course as it's the only way to be sure no lingering drivers or settings are making your system unstable. Or prevent identification of new hardware, if that's your case.

Windows should install default drivers that provide basic functionality for the ethernet port but only if it can identify the NIC.

OH YES and I forgot: have you checked BIOS settings to ensure the ethernet port isn't being turned off? CMOS reset SHOULD leave the motherboard ethernet port turned on but it's a good thing to check.

EDIT ADD: and one last thing you can do before doing the clean install is start Windows in SAFE MODE with NETWORKING SUPPORT. In safe mode Windows uses a default basic driver, but again only if it can identify the ethernet port. With the port turned on in BIOS should the port hardware be defective Windows won't identify it and you won't get internet access (networking support). In that case, you'll have a high degree of confidence it's motherboard hardware.

 

[Kiscvik]

Do a CLEAN install:

https://support.microsoft.com/en-us/help/4000735/windows-10-reinstall

The windows installation process will DELETE all old partitions and re-partition the hard drive. So you have to back up data you want saved. You should do this for a new system (motherboard) as a matter of course as it's the only way to be sure no lingering drivers or settings are making your system unstable. Or prevent identification of new hardware, if that's your case.

Windows should install default drivers that provide basic functionality for the ethernet port but only if it can identify the NIC.

OH YES and I forgot: have you checked BIOS settings to ensure the ethernet port isn't being turned off? CMOS reset SHOULD leave the motherboard ethernet port turned on but it's a good thing to check.

EDIT ADD: and one last thing you can do before doing the clean install is start Windows in SAFE MODE with NETWORKING SUPPORT. In safe mode Windows uses a default basic driver, but again only if it can identify the ethernet port. With the port turned on in BIOS should the port hardware be defective Windows won't identify it and you won't get internet access (networking support). In that case, you'll have a high degree of confidence it's motherboard hardware.

On it right now i will do clean install. All on msi settings is on so no problem with that. I will edit as soon as i get windows back.

 

[Kiscvik]

Do a CLEAN install using only Microsoft's installer:

https://support.microsoft.com/en-us/help/4000735/windows-10-reinstall

Don't use any 2nd or 3rd party utilities, only the Windows installer. The windows installation process will DELETE all old partitions and re-partition the hard drive as it needs to be. So you have to back up data you want saved. You should do this for a new system (motherboard) as a matter of course as it's the only way to be sure no lingering drivers or settings are making your system unstable. Or prevent identification of new hardware, if that's your case.

Windows should install default drivers that provide basic functionality for the ethernet port but only if it can identify the NIC.

OH YES and I forgot: have you checked BIOS settings to ensure the ethernet port isn't being turned off? CMOS reset SHOULD leave the motherboard ethernet port turned on but it's a good thing to check.

EDIT ADD: and one last thing you can do before doing the clean install is start Windows in SAFE MODE with NETWORKING SUPPORT. In safe mode Windows uses a default basic driver, but again only if it can identify the ethernet port. With the port turned on in BIOS should the port hardware be defective Windows won't identify it and you won't get internet access (networking support). In that case, you'll have a high degree of confidence it's motherboard hardware.

Ok after start it on safe mode and reformat all my ssd and install again. Still not working..

 

[drea.drechsler]

Ok after start it on safe mode and reformat all my ssd and install again. Still not working..

It sounds like the NIC hardware is defective. So in warranty, take it back to retailer if you can or contact MSI tech support for RMA. I'd work with the retailer first.

 

[Kiscvik]

It sounds like the NIC hardware is defective. So in warranty, take it back to retailer if you can or contact MSI tech support for RMA. I'd work with the retailer first.

Damm after 1 day ok i will do that Thank you

 

[drea.drechsler]

Damm after 1 day ...

Early failure, or infant mortality as it's called, isn't uncommon.

 

[Krotow]

During last 4 months seen lamenting about sudden network adapter on Realtek RTL8125B chip shutdown in various Internet places. Even in my country tech forums. And not only in B550 motherboards, but also in X570 and in separate network adapters with RTL8125B (MOBO model was Asus Z170-A). OS does not matter. In some cases problem was fixed by replacing Ethernet cable to different category cable (Cat5e to Cat6 or vice versa). Seems something is wrong with RTL8125B chip itself or with reference circuit design for this chip.