Windows 10: Gigabit Network Card is only showing 100mbps in network adapter>status

I'm using 3600+B450 tomahawk max mobo with CAT6 LAN cable plugged in. I'm using Win10 1909 18363.815

All the while it has been 1Gbps until few days ago it keeps disconnecting and reconnecting by its own. And when reconnects it shows 100mbps.

Cable should be working fine as i plugged into my laptop and it shows 1gbps. Could it still be my cable issue?

Things I've done:

bought new router

changed duplex to 1gbps

updated bios

reinstall network adaptor to newest update

:)

 

Network card of Giga and shows only 100mbps on network connections

I've set my jumbo Frame to disabled.





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Still 100 Mbps... ^^

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I've bought a new Network switch of Gigabit and it changed my Network Connections speed to 1 Gbps but still not changed my internet test, it still gives under 100 Mbps.

 

Network card of Giga and shows only 100mbps on network connections

Hi,
I upgraded my internet last week to 200/5 and the day I upgraded I couldn't reach above 100 Mbps.
I started to check why I couldn't and then I thought maybe it's my Network Card and then I just bought a new card and checked if it shows above 100mbps and still it was stuck under 100Mbps so I returned it to the store and stayed with mine because I checked my card and it's 10/100/1000.

I tried to manually set my card to Giga at Device Manager:





And still it showed me 100 Mbps:





I've already tried to update my card but still, nothing worked, I have windows 10 and CAT7 cable, I hope you will be able to help me guys, you're my last way.

 

Network card of Giga and shows only 100mbps on network connections

I've already changed the same kind of router to check if the problem is the router that I got from them, but still gives me 100 Mbps.
Another question, if I have a network card of 1 Gbps, it must to show in the card's name "Gigabit"?