1GB fiber internet speed cut 90%, but ONLY on my PC...??

I had a fiber internet 1GB connection installed about 20 months ago. Its been working like a dream, with a 5GHz router I can stream anything without buffering even on WiFi. My SpeedTest.net speeds have been 950/down and 250/up like clockwork since the day I got the service.

A month ago my PC's download speed got cut off at the knees. I noticed downloads taking much longer than normal and ran a test. It is now at 40/down every single time I run a test, but still (and this seems important) 250/up, just like always. Its only download speed thats effected.

The thing is this problem is ONLY happening on my PC. And, also important, it happens with both the on-board LAN port and a USB 3/LAN adapter I just purchased. Totally separate hardware, exact same results: 40/down, 250/up.

I had a tech from my provider come out and he upgraded me to a brand new fiber box and wireless router. His own taptop tested 950/down, 250/up on the first try. I used the exact same cable and port that my PC uses with my own laptop and got the same: 950/down, 250/up. Even my Galaxy 7 phone gets 250/down, 150/up on a WiFi connection. My X-Box and TV systems are also still at full speed connected with LAN cables.

The PC download speed, however, is gutted. It HAS to be a Windows 10 problem as the issue happens with both LAN connection options--the onboard port and the USB adapter. This happened out of nowhere roughly June 1st. I have not played with any Windows, router, or firewall settings in over a year.

The only things I've done to try to correct this is change the Limit Reservable Bandwidth option using gpedit.msc, and used the "TCP Optimization" software from Speedguide, both of which fixed similar issues for others. It made zero difference.

I have no idea what's causing this. Any ideas? Thanks for your help!

thomaseg1
What is your Lan connector?
Have you updated the drivers recently?
Have you tried uninstalling and reinstalling the the connector in the device manager?

Like I mentioned, the problem is exactly the same with TWO different LAN connections; the on-board LAN port, and a brand new USB 3.0/LAN adapter I just purchased. The drivers are the newest for both. Because they both act the exact same way it seems like it has to be another Windows setting.

Compumind said:

@Kinexus -

Did you try the procedure I mentioned above?

As soon as I have a few minutes to backup my registery I will. :) Not home at the moment, but I'll post when I do. Thanks for the suggestion!

Compumind said:

Windows 10 TCP/IP Reset

1. In the search box on the taskbar, type Command prompt, press and hold (or right-click) Command prompt, and then select Run as administrator -> Yes.

Couldn't even get that far.... I right click and Run as Administrator and nothing happens. At all. It won't let me do it. I've run other commands As Administrator, but can't do a command prompt apparently. No idea why.

bro67 said:

I had to uncheck in the Network Properties the following on the desktop that runs Windows 10 Pro at our house: QOS, Bridge Driver, Reliable Multicast Protocol, Microsoft Network Multiplexor Protocol, Hyper-V Extensible Switch.

With those disabled, my Startech USB adapter set at 1gbps Full Duplex, I now get around 650 with my Gigabit service with Xfinity.

The only one of those I had in my own network settings for my LAN adapter was the QOS Packet Scheduler. I unchecked it, but no different. And Speedtest.net is the site I've been using to test my speed. :)

- - - Updated - - -

Compumind said:

@Kinexus -

Did you try the procedure I mentioned above?

Ok, I was able to run a Command prompt thru the Task Manager. Unfortunately the winsock reset and int ip reset commands killed both my onboard LAN and WiFi connections. Completely. They will not connect to my router, and the WiFi can't see the router (although it can see other WiFi routers near my home for some reason).

When I run the ipconfig /release and ipconfig /renew commands I get this:

"No operation can be performed on Wi-Fi while it has its media disconnected.
No operation can be performed on Local Area Connection* 5 while it has its media disconnected."

Foruntately my new USB 3/Lan adapter wasn't plugged in when I started, so I plugged that in and am back online, but the other 2 onboard network connections (LAN and WiFi) are dead. And my speed is still at 40Mbps on the USB LAN connection, so nothing changed speed wise.

Any thoughts on how to get my ports back?

- - - Updated - - -

Ok, so I ran a Diagnose Problems with the onboard LAN port and it found a DHCP problem, which it fixed, and now its working again.... but the original problem is right where it was. 40Mbps download speed.