[SOLVED] Ethernet capped on one PC and fast on other PC

[bgeo25]

I finally got my PC hooked up to Ethernet to try to get something better than the awful Wi-Fi, but it seems as though my connection might be capped.

During the two tests below, the ONLY main difference was the computer that was connected. Everything else about the setup (Ethernet cables, router, router port) was the same in both cases.

PC #1:

PC #2:

Clearly, I'm trying to use this connection on PC #2, but I can't understand why the network speed is so much worse than on PC #1. The only thing I could imagine it would be is some software-enabled limitation that I don't know about.

• I already checked my netsh configuration, and it's disabled.
• I also tried changing the Ethernet adapter properties Speed & Duplex value from "Auto Negotiation" to "1 Gbps Full Duplex", but that only made it worse, so I changed it back
• I don't have Asus Turbo LAN software installed

Also, the Ethernet adapter status claims that it is running at 1.0 Gbps.

Other information for reference:

• Motherboard: Asus TUF X570-Plus Wi-Fi
• Ethernet adapter: Realtek Gaming GbE Family Controller
• Adapter driver version: 10.46.1231.2020 (latest)

Update: See iperf results below.

 

[SamirD]

I wouldn't use a Internet speed test to determine if your nic is working correctly, I would use iperf locally on your network and see what you get that way. If you get less than 900Mbps that way, then something might be wrong with the wiring.

 

[bgeo25]

I used iperf3 (hopefully correctly) to test bandwidth and the results were stellar on both machines. Both PCs were connected to the same router via Ethernet.

Here are the results from my PC (the one with the slower Internet speed test above). First, it was the server and then it was the client.

D:\Downloads\iperf-3.1.3-win64\iperf-3.1.3-win64>iperf3 -s
-----------------------------------------------------------
Server listening on 5201
-----------------------------------------------------------
Accepted connection from 192.168.1.17, port 50161
[  5] local 192.168.1.177 port 5201 connected to 192.168.1.17 port 50162
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-1.00   sec  83.0 MBytes   696 Mbits/sec
[  5]   1.00-2.00   sec  91.5 MBytes   767 Mbits/sec
[  5]   2.00-3.00   sec  81.3 MBytes   682 Mbits/sec
[  5]   3.00-4.00   sec  81.0 MBytes   679 Mbits/sec
[  5]   4.00-5.00   sec  74.7 MBytes   626 Mbits/sec
[  5]   5.00-6.00   sec  77.0 MBytes   646 Mbits/sec
[  5]   6.00-7.00   sec  81.8 MBytes   686 Mbits/sec
[  5]   7.00-8.00   sec  79.8 MBytes   669 Mbits/sec
[  5]   8.00-9.00   sec  76.9 MBytes   645 Mbits/sec
[  5]   9.00-10.00  sec  76.6 MBytes   642 Mbits/sec
[  5]  10.00-10.04  sec  3.23 MBytes   679 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  5]   0.00-10.04  sec  0.00 Bytes  0.00 bits/sec                  sender
[  5]   0.00-10.04  sec   807 MBytes   674 Mbits/sec                  receiver
-----------------------------------------------------------
Server listening on 5201
-----------------------------------------------------------
iperf3: interrupt - the server has terminated

D:\Downloads\iperf-3.1.3-win64\iperf-3.1.3-win64>iperf3 -c 192.168.1.17
Connecting to host 192.168.1.17, port 5201
[  4] local 192.168.1.177 port 51996 connected to 192.168.1.17 port 5201
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-1.00   sec   111 MBytes   930 Mbits/sec
[  4]   1.00-2.00   sec   113 MBytes   948 Mbits/sec
[  4]   2.00-3.00   sec  99.9 MBytes   837 Mbits/sec
[  4]   3.00-4.00   sec  84.4 MBytes   708 Mbits/sec
[  4]   4.00-5.00   sec  98.5 MBytes   827 Mbits/sec
[  4]   5.00-6.00   sec   105 MBytes   878 Mbits/sec
[  4]   6.00-7.00   sec   102 MBytes   860 Mbits/sec
[  4]   7.00-8.00   sec   104 MBytes   870 Mbits/sec
[  4]   8.00-9.00   sec   103 MBytes   865 Mbits/sec
[  4]   9.00-10.00  sec   107 MBytes   895 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth
[  4]   0.00-10.00  sec  1.00 GBytes   862 Mbits/sec                  sender
[  4]   0.00-10.00  sec  1.00 GBytes   862 Mbits/sec                  receiver

iperf Done.

Does this mean that the wiring is okay?

 

[SamirD]

That's pretty good, but try the -P3 switch and see if it hits 900+ on both in both directions (it should). Otherwise, there might be a bit of a wiring issue causing a minor drop in speed.

 

[bgeo25]

Other online speed tests are showing results between 600 and 700 Mbps for both download and upload. I'm guessing the Google's test uses a far away server (?).

Also, the cables aren't the best of the best, but this is fine for now.

 

[SamirD]

Try using fast.com, dslreports.com/speedtest and librespeed.org and see what you get on those. I've found them to be pretty accurate across different isps.

 

[bgeo25]

Results from Librespeed and others are looking good.

 

[SamirD]

Solid.