RAX20 LAN ports are capped at 100mbs

[R-Kasten]

Hello, my router (info pasted below) does not reliably give me full speed on the LAN ports specifically.  I have 900+mb/s to the modem, and if I plug the ethernet cable (cat6) directly into the modem I get my full plan download speed of 500mb/s.  If I then route the ethernet cable from modem > router, and plug my computer into the router I'll get 500mb/s once, and then 100mb/s afterwards.  If I power cycle the router, I'll get 500mb/s again but then it reverts to 100mb/s.  I've tried all 4 ports and the behavior is the same.

Hardware Version	RAX20
Firmware Version	V1.0.11.112_2.0.77
GUI Language Version	V1.0.11.112_2.1.46.1
Operation Mode	Router
CPU Load	CPU1: 5.00%  CPU2: 4.44% CPU3: 4.27%  CPU4: 1.67%
Memory Usage(Used/Total)	333MB/497MB
Flash Usage(Used/Total)	110.43MB/256.00MB
System Uptime	0 days 19:14:39

[FURRYe38 · Accepted solution]

Be sure the ethernet drivers are up to date as well. 
The RAX only supports up to 1Gb connection rates so you might set a manual connection rate on the adapter for 1Gb only. 

Please mark your thread as solved so others will know. Be sure to save off a back up configuration to file for safe keeping. Saves time if a reset is needed.
https://kb.netgear.com/24231/How-do-I-back-up-the-router-configuration-settings-on-my-Nighthawk-rout...
Enjoy. 📡

[FURRYe38]

What does the speed indicate on the routers web page under Advanced tab/Show Stats button. 
Look at the connection rate for the LAN ports that have connected devices here. 

What is the Mfr and model# of the Internet Service Providers modem/ONT the NG router is connected too?
Be sure your using a good quality LAN cable between the modem and router. CAT6 is recommended. 

[R-Kasten]

The LAN port shows a speed of 100M

I am using a CAT6 cable, and when using that same cable directly from the modem I get 500mb/s. I have fiber internet from Surf and the modem is a :

UFiber loco m/n UF-LOCO.  Thanks for the quick reply.

[FURRYe38]

What is the devices connected at LAN2? 

Does this happen if you switch to other LAN ports? 
Do you have another ethernet supported device to help test with to compare? 

[R-Kasten]

I only use one device on lan, everything else I use wifi for.  The device on LAN2 is my gaming desktop, the same behavior happens on all 4 of the ports. I have a separate desktop that I was fixing for my father, it also gets capped at 100MB with the ethernet cable.

[FURRYe38]

What is the brand and model # of the PC and brand and model# of the ethernet adapter installed in the PC. 

[R-Kasten]

I rebooted the modem and the router for about the 5th time and now I'm getting full speed.  LAN2 is showing 1000M/FULL now, both desktops are using Realtek Gaming GBe 2.5 chipsets.  I'm all set for now, sorry to waste you time.

[FURRYe38 · Accepted solution]

Be sure the ethernet drivers are up to date as well. 
The RAX only supports up to 1Gb connection rates so you might set a manual connection rate on the adapter for 1Gb only. 

Please mark your thread as solved so others will know. Be sure to save off a back up configuration to file for safe keeping. Saves time if a reset is needed.
https://kb.netgear.com/24231/How-do-I-back-up-the-router-configuration-settings-on-my-Nighthawk-rout...
Enjoy. 📡