Question What would cause this network problem ?

stinkbomb

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Dec 5, 2009
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I have a Plex PC in the living room and my main PC is upstairs. The are no problems at all with my Plex PC, it's only affected the other one. It's been going on since December after a Windows update. But within the past week I've basically only had about 5 hours on Internet up there. I'd be playing or browsing and suddenly the connection would drop and I would get different reasons why on Windows like no cable plugged in, restart Ethernet adapter driver, something with dhcp, another with DNS. Don't remember what those said exactly of the top of my head. It was tolerant when it started but now it barely works while my Plex PC is unaffected on the same network.

I've already tried multiple things. Resetting modem/router, switching ports on those, Verizon support and they say nothing is wrong on their end, new cables, bought a network card for the first time in case it was the motherboard port, and last week I wiped the c drive thinking it was a Windows issue and installed bazzite and it still happens on there with a fresh installation. A user in a different forum said it might be unrelated but a gigabit switch solved a weird issue they were having. I bought one, didn't help. Static IPS are all different, someone else suggested maybe two devices were trying to use the same which wasn't the case. Replies stopped there so I thought I would post here instead.

I have the Verizon g1100 router, their ONT I-211M-L, my motherboard is x670 gigabyte aorus elite ax, 7800x3d. I'm thinking it's just something hardware related at this point.
 
I have a Plex PC in the living room and my main PC is upstairs. The are no problems at all with my Plex PC, it's only affected the other one. It's been going on since December after a Windows update. But within the past week I've basically only had about 5 hours on Internet up there. I'd be playing or browsing and suddenly the connection would drop and I would get different reasons why on Windows like no cable plugged in, restart Ethernet adapter driver, something with dhcp, another with DNS. Don't remember what those said exactly of the top of my head. It was tolerant when it started but now it barely works while my Plex PC is unaffected on the same network.

I've already tried multiple things. Resetting modem/router, switching ports on those, Verizon support and they say nothing is wrong on their end, new cables, bought a network card for the first time in case it was the motherboard port, and last week I wiped the c drive thinking it was a Windows issue and installed bazzite and it still happens on there with a fresh installation. A user in a different forum said it might be unrelated but a gigabit switch solved a weird issue they were having. I bought one, didn't help. Static IPS are all different, someone else suggested maybe two devices were trying to use the same which wasn't the case. Replies stopped there so I thought I would post here instead.

I have the Verizon g1100 router, their ONT I-211M-L, my motherboard is x670 gigabyte aorus elite ax, 7800x3d. I'm thinking it's just something hardware related at this point.
Have you carried the PC downstairs and tested with a short, new commercial cable? That is what I would do. Is there in-wall cabling connectingnthe upstairs to the downstairs? If so, that would be the place to start troubleshooting.
 
There's no in wall cabling, it was a 100 foot cable that the Verizon guy gave me 5 years ago until I bought a new 50 foot cable maybe two weeks ago. The case is an old caselabs m8 and water-cooled with 2 rads but I'll try to carry it down and see what happens. I'll update in a bit.
 
It is all going to depend on how long it drops. If it is even a few seconds you have time to issue a few commands and look at lights.

The best one is going to be the simple IPCONFIG /all. Key here will be if there is some kind of physical issue the port will go disconnected.

If the port stays in a connected state then it is more likely some software issue but it still could be a hardware issue if it is just getting lots of data loss....which windows does not seem to track.

It might just be coincidence that it failed close to a windows update. Microsoft though must have massive number of idiots who work there. It has happened a number of times for them to update hardware drivers with actual older drivers...video cards in particular. There is a option they bury that tells it not to do driver updates. I doubt this is the issue. There haven't been any real new ethernet chipset for a few years. Lots of issue when 2.5g ports were new.

In any case figure out which chipset the ethernet is using and go to the chipset vendors site and use that driver.

The most common cause of ethernt problem is bad cables. There are massive amounts of fake cable sold, that flat cable is one of the commonly fakes. You need nothing real special cat5e but it needs to be pure copper with wire size 22-24. The only cable worth paying extra for is cat6a if you have 10gbit everything else will not run better or faster than cat5e.
 
Brought the PC downstairs, still having connection issues with the cable that I use for my Plex PC which never has any down time since I built it close to a year ago. I'm currently on bazzite so I can't use the same ipconfig cmds. Once I'm able to get a connection and this computer, I'll try getting a driver for the chipset but that was something I tried in the past which didn't help. I just forgot to list it in things I've tried.
Edit: I'm just out of ideas before just draining the loop and testing the motherboard and CPU at my brother's since he has the same. It got much worse the past 2 weeks. It was tolerable enough until then.
 
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Your case and cooling system and such are extremely unlikely to be causing this kind of issue unless there is a short which would probably cause other damage you'd notice. At best maybe a power supply problem could make things flaky but you'd be seeing worse problems if that was the issue. You don't need to take anything to another location to test that. Just take the board, cooling, GPU and power supply out of the case and run them on a tabletop. (I don't know why you'd need to take it all apart to test it at your brother's house.)

Get updates for network controllers, motherboard chipset and CPU, video card, everything. Then you need to do more in-depth monitoring and checking of logs since it seems like you just glanced over them. I assume when you plugged it in downstairs with the Plex's cable, you left that cable plugged into its original port on the router. You could get a very inexpensive router to see if the issue is the G1100, and with such low speed you won't notice any performance difference. (Or borrow your brother's router for a short time, or take yours to his house and see if he has problems, if you meant he has the same service.) Given that you've used a different OS, different network card, different cable, in a different location, it doesn't seem like it could possibly be your computer.
 
No problems with the power supply here. I would take it apart since I wouldn't bring over my GPU which is in the loop too, plus I could use new water anyway. Any router port with any cable does the same thing, just on this computer. Nothing else on the network is affected, I've tried every combination with it. Earlier today I had almost 20 minutes with a connection until it stopped working properly. I've seen posts about faulty cpus and motherboards affecting this so that's what I was going to narrow down with trying it over there just to cover everything.
 
Brought the PC downstairs, still having connection issues with the cable that I use for my Plex PC which never has any down time since I built it close to a year ago. I'm currently on bazzite so I can't use the same ipconfig cmds. Once I'm able to get a connection and this computer, I'll try getting a driver for the chipset but that was something I tried in the past which didn't help. I just forgot to list it in things I've tried.
Edit: I'm just out of ideas before just draining the loop and testing the motherboard and CPU at my brother's since he has the same. It got much worse the past 2 weeks. It was tolerable enough until then.
A couple more things to check. #1 -- does your motherboard include any network "optimization" software. An example is Asus "Game First" software. That can cause problems. #2 -- Boot a portable linux from a thumb drive. That will remove Windows completely from the equation.
 
Windows is out of the equation, the drive has been wiped a while ago and I'm running bazzite. I thought it was a Windows problem which is why I switched to Linux. My motherboard has software like that, but for Windows. Says no official Linux version
 
The Windows update was obviously coincidental, since it's happening even under Linux. There could just be some degradation on the motherboard when you see a problem getting worse like this, but it's such a SPECIFIC problem that it's hard to think what it could be.

My last possible thought is that there is a fault in the motherboard affecting the PCIe lanes/power from one of the chipsets (X670 is a dual chipset), since the built-in network controller and an add-in PCIe controller would be using that, and you may not be using any other devices that pass through those. In that case, a USB adapter COULD possibly work, if it's connected to a USB port driven by the CPU instead of the chipset. You'd need to use something like USBTreeView (or Linux equivalent) to test ports with a keyboard or flash drive or something to determine which ports on the board are connected through the CPU or chipsets.

Looking at the motherboard diagram, some of the USB ports go through the CPU, some through the upstream chipset, and some through the downstream, while the 2nd and 3rd PCIe slots are on the downstream chipset. The on-board network controller is also passing through the downstream chipset's PCIe lanes, which could mean there's an issue with the devices through that chip specifically, but the upstream chipset could be fine. Depending on what the issue is, even a USB port through the downstream could be fine, since USB uses an integrated controller, so any PCIe issues wouldn't affect them, unless the uplinks between the two chipsets and/or the CPU were affected or the chipset fault affected more than just PCIe.

Do you have anything other than a GPU and an NVMe SSD installed normally? Try to see which USB ports your keyboard and mouse use, using USBTreeView or equivalent. It could be that you've just been using everything through the CPU the whole time including USB devices, except for the network port, and it could be either of the chipsets at fault since issues with the upstream would affect the downstream.
 
Yeah once it started happening on Linux, I knew it wasn't Windows. It took about 2-3 hours to drop a connection that day so I originally thought it was. Thanks for the detailed post. I've had 2 nvme's installed for years, only one GPU and now this network card. It was fine yesterday with the USB adapter but now it's dropping. I'll look for a Linux equivalent and check it the usb stuff you mentioned.

Edit: I switched USB ports and it didn't drop since but I'll see how it is for a day or two. Longest I've went without the connection dropping was about 2 days.
 
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I am not sure if you answered this above. Do you know if the ethernet port is actually going down/disconnect or does it not just pass traffic. If the port does not go down then it could be some issue with DHCP or ARP/mac addresses. I have not used linux in a while so I forget all the commands.
 
I'm not the most experienced with Linux, just tired with Windows so I don't know all the commands either. But when this was happening on Windows, the normal connection symbol in the tray would change to the circle with lines meaning no connection. The error would say different things, like no Ethernet cable plugged in, restart your Ethernet adapter, something about the DNS server, and another about DHCP. Don't remember what those said exactly. On Linux, it would say connected to a network but the Internet is unreachable. The USB to Ethernet send better but I need more time with it to know for sure. Only dropped one with it so I switched USB ports.