RT-AC3200 half speed since update

[stewie3128]

Today upgraded from 380.68 to current 384.10_2 on my RT-AC3200. Reset all settings after flash, recreated them from screenshots, and I'm getting at-best 450mbit on my gigabit fiber connection. Earlier today I was averaging 890-910 from Fast.com, and high 700s from dslreports.

My ATT modem (which unfortunately I cannot remove from the chain for ATT reasons) has an internal speedtest to the ATT network and it shows 975 downstream and 915 up, which is the same as it was earlier today.

I've noticed that the center of the unit's cover is hot to the touch. Current CPU temp is 66C/151F, both radios are in the 50C/120F range, and all have been stable there for at least several hours.

QoS is off, firewall is on (though when I turned it off I saw a consistent 30-40mbit improvement), CPUs are hanging out around 0-4%, don't know what other salient bits to report. I can upload the CFG file if that would help.

Is there anything obvious I can do to diagnose this?

 

[Zastoff]

NAT-acceleration turned off?

 

[stewie3128]

NAT-acceleration turned off?

Turned it off as part of the troubleshooting, no apparent effect on either CPU or throughput. It’s currently off.

 

[L&LD]

The RT-AC3200 (1GHz), along with the much higher clocked RT-AC3100 (1.4GHz) can't do Gbps connections without HW acceleration on.

When upgrading from such an old firmware, I would recommend that you don't copy all 'screenshots' religiously.

Leave the router at full defaults and proceed cautiously. Testing as you go.

The reason is that what we think we once 'knew', changed in the meantime. Along with the changes in the latest features, tweaks and possibly new defaults in a vastly more recent firmware version.


Coming from such an older code base:

I would 'format jffs on next reboot' and reboot at least two times (waiting 5 minutes in between), perform a proper WPS NVRAM erase and then re-flash the latest firmware once again and then reset to factory defaults via the GUI.

Now, use new SSID's (you can reuse your old passwords) and leave most options at default, changing only if testing proves to be better.

See my signature for links and more details on the above steps.

 

[stewie3128]

Thanks much L&LD, I followed your guide and it's back up to where I expect it to be on all the different speed tests, and even got an A+ in Bufferbloat from dslreports! First time on ATT.

I don't know if there was any secret junk in JFFS or what, but it worked.

Thanks again!

 

[stewie3128]

Here's my latest speed test.... for reference, I'm paying for symmetrical gigabit from ATT fiber. Thanks again for the M&M guide!