R6700v3 Wired Connection ~200Mbps

[dpmoore]

I bought this router in January 2021.  After I set it up, the wired speeds tested out at ~800Mbps.  So, I know it was working as expected and that was before I upgraded to the 1200Mbps package.  I regularly update firmware on my devices for security purposes.  Somewhere along the way I have dropped down to ~200Mbps.  Xfinity has been out and tested the connection out of the modem and it is as expected. 

I have not had a chance to further troubleshoot until now.  I tried to open a support ticket, but I am past the 1yr support window.  From reading these forums, it sounds like a firmware issue introduced somewhere along the way (consistent with my experience).  This is my last ditch effort before I submit a warranty request since I consider the router now defective.

Here is my setup:

Xfinity Modem CM1000V2

R6700v3 Firmware: just updated to v1.0.4.122

All disabled: Access control, traffic monitoring, parental controls, qos

[dpmoore · Accepted solution]

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@FURRYe38 wrote:

Has a power off for 1 minute then back ON with the ISP modem and router been performed since last update?

No.  I will try that before the factory reset though.  Thanks

Has a factory reset and setup from scratch been performed since last FW update? No.Will try tonight

If any of these suggestions don't seem to help, you may need to revert back FW to what had been working. 

That is non-starter for me due to security concerns.  Unit is defective if I cannot maintain max speeds with latest FW

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[plemans]

Have you tried a factory reset and then tested speeds with the router in the default configuration? 

Reason I ask is the R6700 uses cut through forwarding to hit gigabit speeds.

The access control, traffic monitoring, qos, parental controls all disable it. And even after disabling those services, I've seen ctf not get re-enabled. So speeds stay slow.

So try a factory reset and test the speeds with the router in its default configuration. If it test full speeds, then start setting up your services with testing the speeds each time you change something. 

[FURRYe38]

Has a power off for 1 minute then back ON with the ISP modem and router been performed since last update?

Has a factory reset and setup from scratch been performed since last FW update? 

If any of these suggestions don't seem to help, you may need to revert back FW to what had been working. 

[dpmoore]

I have never enabled access control, traffic monitoring, qos, parental controls.  I think the only thing I changed in the setup was to disable the Guest networks.

I have not tried a factory reset.  That would be my last resort which seems I am there.  I presume that will keep the latest Firmware version intact?

I will try the factory reset later tonight (have to work) and report back.

Thanks

[plemans]

It'll keep the current version of firmware intact. 

It only removes settings. 

If that doesn't work, then we can try other versions of firmware. 

[dpmoore · Accepted solution]

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@FURRYe38 wrote:

Has a power off for 1 minute then back ON with the ISP modem and router been performed since last update?

No.  I will try that before the factory reset though.  Thanks

Has a factory reset and setup from scratch been performed since last FW update? No.Will try tonight

If any of these suggestions don't seem to help, you may need to revert back FW to what had been working. 

That is non-starter for me due to security concerns.  Unit is defective if I cannot maintain max speeds with latest FW

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[plemans]

Also, try enabling ipv6 on the router if it initially tests low. 

What site/app are you using to speedtest with? 

And what device? 

[dpmoore]

I will add ipv6 to my troubleshooting list.

I have always used speedtest.net.  I have tested using Lenovo T14 laptop and an older Dell Desktop.  Both have 1Gb ethernet controllers 

[plemans]

Ok. let us know how the reset/ipv6 goes after you get a chance. 

Hope it works for you!

[dpmoore]

ok..I am perplexed...

1. Power off the R6700v3 and removed power from the CM1000V2 modem for 1+ minutes.  Powered on the modem until all the LED's were green, then powered on R6700v3.  Same result ~200Mbps.

2. R6700v3 factory reset.  738Mbps... much progress!

3. Enabled ipv6.  902Mbps... Yes!

4. Changed the SSID's and passwords back to what I had previously. ~250Mbps.... WTF?

Why would the SSID's/passwords affect the Wired Ethernet speeds???

[dpmoore]

I think #4 was a fluke.  I am now back up 800+Mbps the last few tests.  I will test again in the morning

[michaelkenward]

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@dpmoore wrote:

I think #4 was a fluke.  I am now back up 800+Mbps the last few tests.  I will test again in the morning

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Speed tests aren't as "scientific" as you might think. They depend on too many factors.

When I want to have fun, I run a sequence of half a dozen tests on different sites. They can deliver results that are all over the place.

[plemans]

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@dpmoore wrote:

I think #4 was a fluke.  I am now back up 800+Mbps the last few tests.  I will test again in the morning

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either way I'm happy you have your speed back. 

Nice to see. 

If it stays 800+ you can mark it as solved so others aren't trying to fix it 🙂