[SOLVED] What keeps slowing my gigabit connection to 100 mbps

Brad Magnus

Honorable
Jul 19, 2014
38
0
10,530
My Killer E2200 Gigabit keeps getting downgraded to 100mbps after the system has been running for a few minutes. I'm running Windows 10 v10.0.18362. TP Link Archer A7.

When I first boot the system, I open up the Control Panel Double Click the Connection and it shows 1.0gbps. Speedtest confirms I'm getting my full 400mbps from the ISP. Then 30 minutes or less later, I check again and it's been capped at 100mbps. Duplex is set to Auto Negotiate. I've restarted modem and router. What am I missing?
 
Solution
Why do you think its a flat ethernet cable? (which I do have) Nothing in the walls. It's a small office.
Because "flat" ethernet cables have wires that are too thin to meet the spec. They need to be 22 to 25 gauge to be reliable. Replace that flat cable with a quality all copper 22 to 24 gauge cat5e or cat6a cable and you will stay at gigabit speeds.

kanewolf

Titan
Moderator
Why do you think its a flat ethernet cable? (which I do have) Nothing in the walls. It's a small office.
Because "flat" ethernet cables have wires that are too thin to meet the spec. They need to be 22 to 25 gauge to be reliable. Replace that flat cable with a quality all copper 22 to 24 gauge cat5e or cat6a cable and you will stay at gigabit speeds.
 
Solution

Brad Magnus

Honorable
Jul 19, 2014
38
0
10,530
Also......

Speed & Duplex

"Duplex is set to Auto Negotiate."

Set manually and configure Value to 1.0 Gbps Full Duplex

Click the small downward pointing arrow on the right side of the "Value:" box.

No auto.

That is not what Killer support suggests. I was surprised to see that the other day when I was on their site. Thanks though, it was the cable.
 

Brad Magnus

Honorable
Jul 19, 2014
38
0
10,530
Because "flat" ethernet cables have wires that are too thin to meet the spec. They need to be 22 to 25 gauge to be reliable. Replace that flat cable with a quality all copper 22 to 24 gauge cat5e or cat6a cable and you will stay at gigabit speeds.
Thanks for the comment! Turns out it was the cable. However that exact cable has been good for quite some time. Maybe it's been damaged. I swapped it out for another not flat cable and we're back to the races. Now I gotta get a longer not flat cable.