Windows 10: 2 PCs, one slowing down internet of other !

This is ultra strange. I have 2 PCs. For the last 3 months I have been having issues where just one of the PCs internet would slow down from the usual 60mbps to 20mbps or less (only on single thread, multi-thread was fine). Normally the first 2 minutes of the computer being turned on the speed would be fine, then it would slow right down. For months I tried to diagnose the problem, I tried 3 different USB3 to Ethernet adapters just in case my NIC was at fault. I bought another NIC card just in case. I turned off various services and uninstalled software. I changed ports on my gigabit switch, I tried direct connected to router, I tried a new 5e cable, cat6 cable, etc. Then when my slowed PC broke the other day I got a new PC (except for the hard drives and PSU and USB3 card and graphics) and was slightly relieved I had an excuse to finally end this problem as I assumed my motherboard was causing it, and yet the problem STILL exists, even with a fresh Windows 10 installation on a new PC (motherboard, CPU and memory was new).

So one thing I never tried was turning the other PC off that is connected to the network, it runs 24/7. I didn't turn it off before to test because the speed was perfect on that computer, always a rock solid 60mbps. So I ignored it thinking that can't be the cause. Then today when I was at my wits end, given the new PC has the same issue, I decided to turn off the other PC. Then I found the speed was finally normal, talk about a massive face palm. But what the hell does this mean ? Why is a PC that shows a rock solid 60mbps (which is the max speed of my internet) in both single and multi-thread the likely cause of the internet speed on my other PC being slowed down in single thread ?

Is there any logical possible cause ? Some kind of loopback issue ? Both have the same hotmail username. Both sync OneDrive and settings. Both are Windows 10 Pro. Both are Ryzens (although my last PC was an i7 and the same happened with that).

One thing to note, if I manually disable and then re-enable the network adaptor on the slowed down PC then I get full speed for approx 1 minute before it slows again.

:)

 

WIN10 internet SLOW!!!!!!!

Hello William,

We realize the inconvenience you are experiencing with slow Internet Connection. We will certainly help you.

• Have you installed all pending Windows updates?
• Have you tried connecting to some other Internet connection and check if the same issue occurs?

We suggest you to connect your system to some other network and check if the same slow Internet connection issue persists. If no then there must be issue with your Internet connection.

Further you can try performing the steps from the link below and check if it helps:

Fix network connection issues

Let us know the status of the issue. We will be happy to assist you further.

Thank you.

 

Slow Internet only on PC.

Hi,

There are a lot of things that affects the speed and performance of your device. Your PC may become very slow when infected by virus and malware or when device's memory space is almost full. To isolate your concern, we'd like to ask the following questions:

• What is the make and model of your device?
• Which Windows version are you using? Type winver in the search bar and press
  Enter to find out.
• Is your device still slow even if it's disconnected from the internet?
• Have you made any recent changes on your device prior to the issue?
• What have yo done so far to to resolve the issue?

Meanwhile, we suggest that you perform the methods recommended by Prabhavathi Patil in this
thread to boost your device's performance.

Kindly update this thread with the results.

 

Constant script errors and slow loading pages in 10 internet explorer 11

I have done the steps listed above. They have not helped and I am still getting constant script errors, along with slow loading pages. Are there any other suggestions?