Question PC not getting full speed over wired connection - Bad Ethernet port?

[CubsWin]

After upgrading my Xfinity plan to 900 Mbps last week, I have been pulling my hair out trying to figure out why I'm not getting close to that speed on my Windows 10 machine.

Through process of elimination, I have ruled out the router and the cabling. I have tried multiple different modems, all capable of multi-gig speeds, and all with very similar results (about 600 Mbps on average). Xfinity has been out to my house twice and verified all the signals. After the first visit, they recommended I get a different modem, but that didn't solve the problem. During the second visit, they tested the speeds at every point in the chain and were able to show me that the modem is sending a consistent 950 Mbps to the PC.

That got me thinking that maybe it is the ethernet port itself that isn't capable of handling the additional speed. I don't have any other computers in the house, but I realized I could run a speed test on my wired Xbox Series X, which returned 900 Mbps. Then I dug a cheap USB to Ethernet adapter out of my closet and connected that to my main computer again, and I got readings right around 900 Mbps again. So my onboard ethernet definitely seems to be the problem, but why?

I have an ASUS Maximus IX Hero Z270 motherboard, which has an Intel I219-V ethernet connection. I checked that the drivers are updated and also updated my BIOS and confirmed the settings there. I have ordered a cheap PCIE NIC that I'm hoping I can squeeze into my one available PCIE slot (it's going to be a real tight fit next to my CPU cooler). Assuming I can fit it in the slot, I'm hopeful that will solve my problem. Other than installing a new card, is there anything else I could be doing with my onboard ethernet port to try to solve the problem? Or is it just showing its age at nearly 6 years old?

 

[BFG-9000]

It's all the CPU offloading stuff you have to disable. Those really haven't been relevant since Pentium 4 when 1gbit transfers on something like a DL-2000 or National Semiconductor NIC would use an entire GHz worth of single-core CPU for each direction.

In any case Intel has a help page about it.

 

[kanewolf]

I have an ASUS Maximus IX Hero Z270 motherboard, which has an Intel I219-V ethernet connection. I checked that the drivers are updated and also updated my BIOS and confirmed the settings there

Updated from where? Asus website or Intel website for the 219 driver?
Have you checked the Windows Autotune setting -- https://www.ghacks.net/2016/08/05/windows-10-limiting-internet-speed/
You could try TCPOptimizer -- https://www.speedguide.net/downloads.php

 

[CubsWin]

It's all the CPU offloading stuff you have to disable. Those really haven't been relevant since Pentium 4 when 1gbit transfers on something like a DL-2000 or National Semiconductor NIC would use an entire GHz worth of single-core CPU for each direction.

In any case Intel has a help page about it.

Thank you for the information, but none of those settings seem to make any difference whatsoever in my speed tests.

I should note though that I'm getting 930 Mbps in Safe Mode, which seems to match what is being described on that help page. It just doesn't seem like any of those settings are fixing it. But there must be "something" that is the preventing the card from reaching the speed when not in Safe Mode.

 

[CubsWin]

Updated from where? Asus website or Intel website for the 219 driver?
Have you checked the Windows Autotune setting -- https://www.ghacks.net/2016/08/05/windows-10-limiting-internet-speed/
You could try TCPOptimizer -- https://www.speedguide.net/downloads.php

Updated from the ASUS website first and tested, then updated from Windows update (which was a newer version), then updated directly from Intel (which was a newer version still). None of the driver versions improved my speeds. Disabling autotune did not help either.

 

[CubsWin]

I have made a new discovery that I have no idea what to make of.

I have a few applications on my PC that are running almost all the time. Three of them are:
Elgato Sound Capture
Mozilla Thunderbird
MusicBee

When I kill all 3 of those apps in Task Manager, then I get my full 930 Mbps speed. But if any one or more of those applications are running, then I get anywhere between 400-600.

What on Earth could that mean?

Final update before I go to bed:
I should note that I have been running all of these tests in Chrome and Edge. I ended up downloading the Okta Speedtest Windows 10 app and that one is showing over 900 Mbps consistently regardless of which apps are or aren't running. So I guess the question now is why aren't my browsers seeing that full speed (in either speedtest.net or Xfinity speed test) unless I kill all the applications listed above?

 

[bill001g]

I doubt it is all three apps but you never know with windows.

I would watch the resource manager and see if anything stands out from these apps. You would think they would use no network bandwidth at all so it would have to be something else like maybe a memory or cpu issue.

More important does this actually have any impact on your normal usage. Most people do not actually need/use internet at 1gbit. The ISP know this and it is why they can get away with selling lots of people the same 1gbit of bandwidth because they know they will not all use it at the exact same time.

The only application that can use 1gbit is file downloads which is a very small percentage of the traffic for most people. What rates do you get on say something like steam. Note steam in MBYTES/sec by default so the most you will see is 125MBYTE/sec.

For most other things the high speed makes no difference. For stuff like say netflix or youtube it runs at a much slower rate (likely under 50mbps) no matter how much faster your internet is. Things like web browser etc are transferring very small amounts of data where the overhead in much higher than the time it takes to transfer the data. You in general will not be able to detect much difference in a web browser between a 100mbps and 1gbit.

 

[CubsWin]

No, I don't "need" the additional bandwidth in the browser, but I would still like to understand what is happening and if there is an underlying problem (other than needing a new PC).

I suspect that the issue with the 3 applications isn't unique to those applications, but they just happen to be the ones that are running. They are all showing extremely low CPU, disk, and network usage. It could be something with the way the CPU cores are being managed when other applications are running, but I'm not sure why that would be the case, and why that wasn't the case when I used a USB ethernet adapter.