RT-N66U unable to utilize 300mbps Internet Service?

[ckelley87]

Hi all, lurker for awhile but am stuck and need to see if anyone else has the same issue or a solution/thoughts.

I live in Austin and use Time Warner Cable, we were recently updated to 300/20 service thanks to competition with Google Fiber and AT&T U-verse. I bought and received my brand new SB6183 to utilize the full speeds and was super excited to utilize the full speeds available.

From the SB6183 to a Retina MacBook Pro through a USB3 to Gigabit adapter, I'm getting beautiful speeds: 309 Mbps down and 21 Mbps up. Fantastic.

Plugged the 6183 into my RT-N66U, went over to my desktop, all connected via Cat 5e, showing Gigabit connection to the router... and I can't get over 120 Mbps down or 9 Mbps up. Not fantastic. Switched to another outlet in the house, same thing. Used same USB3 to Gigabit adapter and re-tried on MBP, same thing. New wire from router to MBP, same thing. Okay, what the?

I opened up the Admin panel and saw that when running a speed test, I'm maxing out the CPU the entire time. Is the CPU not fast enough for that kind of internet speed? I know it's had no problem handling local traffic, including large files across our home network, but this is a first that I'm seeing something like this (obviously because I've never personally had a connection so fast).

Does anyone have any feedback or tips? Anything appreciated! Thanks!

Edit: Disabled QoS, peaked the speed test at 211 Mbps down and 21 Mbps up, so that's an improvement already. Firmware version is 3.0.0.4.376_2524, official ASUS stuff. Saw some things about a "Merlin" firmware, if that will help I'm all for giving it a shot. Still working towards 300, so any feedback would be appreciated.

 

[L&LD]

Check that the NAT acceleration is on and if it's not, undo the option that disables it.

QoS is only one feature that could disable NAT acceleration.

With NAT acceleration on, you should be able to max your ISP speeds. Especially on a wired LAN connection. Wireless will depend on many factors, mostly decided on environmental 'noise', number of device antenna (you'll need three) and actual device itself (a laptop will more easily hit those speeds than a phone or ipad will, for example).

 

[ckelley87]

Thanks LL&D. I checked and NAT Acceleration was enabled. For fun, I disabled it and tested, didn't see a big drop in speeds (only about 3-5 Mbps), but then turned it back on. I also enabled jumbo frames, but it did not appear to have any effect either.

I did have it peak at 226 Mbps, and 226 Mbps is obviously more than enough for my needs, I'm much more excited for the upload improvements. Will continue to investigate other routers as well, though I'm not keen on spending $250+ on a new one anytime soon.

 

[L&LD]

Not only do you need to check that NAT acceleration is enabled, you also have to check it is actually being used.

Go to Tools and scroll down to Network section to see if HW Acceleration is really on or not.

 

[fttp]

Hi ckelley87, yes the Asus RT-N66U can utilise 300Mbps services. I have 330/30 provided in the UK by Plusnet. You need to ensure that NAT Acceleration is turned on - and is actually on!

Recently my speeds had dropped from around and average of 270Mbps down to 100 - and up had stayed at 30. Yesterday after connecting directly to the ONT and bypassing the router I got in the 200s and therefore realised the router wasn't at fault. I then trawled the internet for a solution.

I found it wasn't a recent change in the firmware that was at fault - I use Asuswrt-Merlin (version 3.0.0.4.376.47_0) - but that I'd enabled IPTraffic under Traffic Monitoring (under Tools, Other Settings, Traffic Monitoring, Enable IPTraffic (per IP Monitoring)).

This turned off Nat Acceleration and even if you turn Nat Acceleration back on under LAN, Switch Control, it is still turned off. I discovered this when I looked under Tools, Sysinfo, Network and next to HW Acceleration it said HW Acceleration is disabled - Incompatible with IPTraffic. (HW Acceleration and NAT Acceleration are the same thing; both names are used in this version of the firmware). So this pointed me to turning off IPTraffic.

Note when making changes to IPTraffic the router needs to be rebooted to enable HW Acceleration again - clicking Apply doesn't work.

I've put all this detail into this post to help others with internet speeds of over 100 - 120Mbps who may be having similar problems - there aren't a huge number of posts due to the relatively few people with the faster speeds.

I've seen speeds above 300Mbps with the Asus - there's no need to buy a replacement. I use a SamKnows Whitebox which monitors my internet connection so I can see the performance over the past year - thus I knew speeds had dropped down recently.

If the Asus firmware doesn't work I recommend using the Asuswrt-Merlin firmware as I know it works!

 

[Slamb]

Just for info, lower model (RT-N56U) can handle 1 Gb/s without problem, so RT-N66U must do the job as well... I have exactly same speeds with and without the router, so no need for upgrade...

 

[pachocco1]

Same problem here.

I have the same service, symptoms and router however I am using Merlin 3.0.0.4.376.47_0.

I get 130 Mbps Down / 20 Mbps Up
~~~~~~~~~~~~~~~~~~
QOS off.
Enable IPTraffic (per IP monitoring) No
NAT Acceleration Enabled

Individual Items
~~~~~~~~~~~~~~~~~~
VPN Tunnel (Turned off with no effect)
Transmission (Turned off with no effect)
DNS Filter (Turned off with no effect)

Parental Controls (Turned off with Increase in Download to 155 Mbps)

Will play around with this and report back any findings.

 

[jontalk]

To jump in here as an Asus noob and having just returned an Asus refurb N66U, I have the Comcast 100 mbps service using my own SB-6141 modem (which totally rocks btw). When I set up the Asus which was running Merlin 374.49 the best speed I could get was around 94. My 7 year old Netgear WRN3500 was consistently getting 125+. That pissed me off right away. To add make it worse, the Asus wouldn't hold the modem connection after running 3 days so it went back. I also noticed that even with the stand mounted it ran VERY hot.

All the reviews say this is one of the best routers, but it appears you either have to have them set up right or be lucky you got one that had good QC.

 

[RMerlin]

To jump in here as an Asus noob and having just returned an Asus refurb N66U

All the reviews say this is one of the best routers, but it appears you either have to have them set up right or be lucky you got one that had good QC.

You said yourself it was a refurb, so the QC you talk about doesn't really apply here. Refurbs are always a gamble, regardless of the manufacturer.

 

[jontalk]

You said yourself it was a refurb, so the QC you talk about doesn't really apply here. Refurbs are always a gamble, regardless of the manufacturer.

Yes this is true with regard to the refurb device. But the question remains that this thread was posted by someone that has a NEW device that was having the same experience with slow throughput, correct?

I'm willing to gamble again, but I guess I need to hunt for a new one or at least one with minimal use. Like any smart shopper, I prefer a good deal especially on a device that isn't a 2014 model.

 

[pachocco1]

Factory Reset

Posted earlies about not getting full speeds.
Did a full factory reset and have it now.

Last Result:
Download Speed: 325043 kbps (40630.4 KB/sec transfer rate)
Upload Speed: 21903 kbps (2737.9 KB/sec transfer rate)
Latency: 7 ms

Will start from here and see what features/services I add reduce Dload capability.

 

[jontalk]

Posted earlies about not getting full speeds.
Did a full factory reset and have it now.

Last Result:
Download Speed: 325043 kbps (40630.4 KB/sec transfer rate)
Upload Speed: 21903 kbps (2737.9 KB/sec transfer rate)
Latency: 7 ms

Will start from here and see what features/services I add reduce Dload capability.

Does this mean you're running Asus firmware or are you using Merlin? Just curious since I've decided to hunt for another one. Thanks.

 

[pachocco1]

Does this mean you're running Asus firmware or are you using Merlin? Just curious since I've decided to hunt for another one. Thanks.

Merlin Firmware. In my case a configuration conflict appears to have been the issue.

 

[ray]

I think TWC recently upgraded my connection to 200/20.

On Wifi next to my RT-N66U running the 374.43 fork of Merlin, I just got a Speedtest of 128.99/21.89.

Is that considered normal for wifi (I understand it'll be impossible to get the max without a wired connection) ?

 

[L&LD]

ray,

It depends on what device you tested it with.

The RT-N66U is capable of 200/20 speeds over WiFi assuming the client is a three antenna Class N 450 design and in the same room and with NAT acceleration enabled in the router.

 

[ray]

Oh sorry I didn't know that. I was testing from a Macbook Air. With that in mind are the speeds I'm seeing normal?

 

[L&LD]

I don't use an air, but considering that it is optimized for long battery life, I would say it is excellent.

 

[ray]

Great thanks! I wasn't sure what's an 'acceptable' drop off with wifi.