What's new

ASUS RT-AC68U Merlin 380.68_2 Poor Download Speeds

  • SNBForums Code of Conduct

    SNBForums is a community for everyone, no matter what their level of experience.

    Please be tolerant and patient of others, especially newcomers. We are all here to share and learn!

    The rules are simple: Be patient, be nice, be helpful or be gone!

shesk

Occasional Visitor
Updated with solution at bottom of this post.

I am re-asking this question in the Merlin forum as I did not have the correct forum category the first time...original post here

I recently switched to CenturyLink 1gbps service and I'm not seeing the full speeds for download. I get 150-250mbps down and 900mpbs upload. I only started getting better upload speeds after I flashed new firmware to my router. A couple things to note:
  • When CL tech came out, using their C2100T (and computer in safe mode...no idea why this was required but the tech insisted it was the only way to see 'actual' speeds) it was showing 950 down and 950 up.
  • I'm using an Asus Gigabit RT-AC68U with Merlin 380.68_2 firmware.
  • I have CAT6 cable running from ONT to the router.
  • I'm testing a wired connection, not wireless.
  • Network status on Ethernet says 1.0 gbps
  • Testing was performed @ speedtest.net and beta.speedtest.net
  • Wireless connection (from phone and laptop) are showing the same download speeds as wired.
  • gigabit fiber with PPPoE
Asus Router settings:
  • Enable Jumbo Frame = Enabled
  • NAT Acceleration = Auto
  • Spanning-Tree Protocol = Enable
  • HW acceleration = Enabled
I'm thinking it is settings specific to my router that are preventing me from getting the full download speed. Any thoughts on what I should change or configure?

Let me know if there is any other information that would be helpful in diagnosing this problem.

Thanks

SOLVED:
RMerlin had mentioned that not all firmware versions play nicely with PPPoE and NAT, I just need to simply find a version that works.
Doczenith1 had a working router doing 940 both directions, so I asked what version he was on updated to that version and it now works. I'm getting 850+ in both directions (I had other machines on the network too so it could have been faster if it was just one comp on the network).

SOLUTION:
Update to Firmware 380.68_0 and hard reboot the router.
 
Last edited:
I am re-asking this question in the Merlin forum as I did not have the correct forum category the first time...original post here

I recently switched to CenturyLink 1gbps service and I'm not seeing the full speeds for download. I get 150-250mbps down and 900mpbs upload. I only started getting better upload speeds after I flashed new firmware to my router. A couple things to note:
  • When CL tech came out, using their C2100T (and computer in safe mode...no idea why this was required but the tech insisted it was the only way to see 'actual' speeds) it was showing 950 down and 950 up.
  • I'm using an Asus Gigabit RT-AC68U with Merlin 380.68_2 firmware.
  • I have CAT6 cable running from ONT to the router.
  • I'm testing a wired connection, not wireless.
  • Network status on Ethernet says 1.0 gbps
  • Testing was performed @ speedtest.net and beta.speedtest.net
  • Wireless connection (from phone and laptop) are showing the same download speeds as wired.
  • gigabit fiber with PPPoE
Asus Router settings:
  • Enable Jumbo Frame = Enabled
  • NAT Acceleration = Auto
  • Spanning-Tree Protocol = Enable
  • HW acceleration = Enabled
I'm thinking it is settings specific to my router that are preventing me from getting the full download speed. Any thoughts on what I should change or configure?

Let me know if there is any other information that would be helpful in diagnosing this problem.

Thanks
Try disabling Jumbo Frames

Failing that, try a factory reset
 
Try disabling Jumbo Frames

Failing that, try a factory reset

Disabling Jumbo Frames did not seem to have any affect on the speeds.

After performing a factory reset, adding PPPoE info and setting up the IPTV VID (CenturyLink settings?) I was surprised to find the Firmware was still Merlin and not the Factory installed Asus firmware.

Either way, speed tests come up with similar results. Latest test was showing 224 down and 810 up.

Any other thoughts?
 
Last edited:
PPPoE and NAT acceleration are often problematic. Every now and then, a change from Broadcom or Asus will break it, and they fix it again a few versions later. You might want to experiment with older firmware versions to compare results.

I know that there's been some changes related to that very recently. Some of these changes were also related to IPv6 and UDP (fixing one thing actually broke the other). Can't remember the specifics, sorry.
 
Also a factory reset doesn't reset the router to the original firmware, it only resets settings you have entered into the router. That's why you still had rmerlin firmware on it after a factory reset.
 
PPPoE and NAT acceleration are often problematic. Every now and then, a change from Broadcom or Asus will break it, and they fix it again a few versions later. You might want to experiment with older firmware versions to compare results.

I know that there's been some changes related to that very recently. Some of these changes were also related to IPv6 and UDP (fixing one thing actually broke the other). Can't remember the specifics, sorry.

Looks like I'll have a long weekend ahead of me trying out different firmware versions. Thanks!
 
For reference my 68U will do 380 Mbps down and 480 up with NAT acceleration turned off. With CTF enabled it will do 940 both ways albeit with core 1 pegged at 100%. This is on a non PPPoE connection.
 
Just try firmware releases based on different GPL versions (look at the changelog). That means maybe 3 or 4 firmware to test at most (don't go any further back than 380.61).
 
For reference my 68U will do 380 Mbps down and 480 up with NAT acceleration turned off. With CTF enabled it will do 940 both ways albeit with core 1 pegged at 100%. This is on a non PPPoE connection.

Mind sharing some additional settings? What firmware are you running? Did you change any other settings to get the 900+ speeds?
 
Just try firmware releases based on different GPL versions (look at the changelog). That means maybe 3 or 4 firmware to test at most (don't go any further back than 380.61).

Very good call, thanks! I'll be sure to review the logs first. Appreciate the help.
 
I run a pretty basic setup the following options changed from the defaults. Running 380.68_0 currently.

AiProtection - Network Protection
All options on

Wireless 2.4 GHz Professional
Turbo QAM - Disable
Airtime Fairness - Disable
Explicit Beamforming - Disable
Universal Beamforming - Disable

Wireless 5 GHz Professional
Airtime Fairness - Disable
Universal Beamforming - Disable

LAN - DHCP Server
Two computers with Manually Assigned IP

LAN - Switch Control
Enable Jumbo Frame - Disable (can’t remember if this is the default or not)
Spanning-Tree Protocol - Disable

WAN - Port Forwarding
Two computers with port forwarding.
 
I run a pretty basic setup the following options changed from the defaults. Running 380.68_0 currently.

AiProtection - Network Protection
All options on

Wireless 2.4 GHz Professional
Turbo QAM - Disable
Airtime Fairness - Disable
Explicit Beamforming - Disable
Universal Beamforming - Disable

Wireless 5 GHz Professional
Airtime Fairness - Disable
Universal Beamforming - Disable

LAN - DHCP Server
Two computers with Manually Assigned IP

LAN - Switch Control
Enable Jumbo Frame - Disable (can’t remember if this is the default or not)
Spanning-Tree Protocol - Disable

WAN - Port Forwarding
Two computers with port forwarding.


That did it. I changed the firmware to 380.68_0 and I'm getting 850+ both directions. Thanks!
 

Latest threads

Sign Up For SNBForums Daily Digest

Get an update of what's new every day delivered to your mailbox. Sign up here!

Members online

Top