N66U - Shocking 2.4Ghz performance all firmwares 3.0.0.3.151 and above ?

[thewusman]

Hi all

Looking for some advice here.

Disclaimer: I can only get my Huawei E372 3G usb modem working on firmwares above .151 including Merlin's so I'm stuck using the latest releases.

However, on the same range of firmwares my 2.4Ghz performance is basically dead on the following 2 devices:
- 2012 Macbook air
- TP-Link TL-WN822N 300M Wireless High Gain USB Adapter

I use the TP-link as my XBMC windows 7 streaming receiver and the connected rate has fallen from around 240-300Mbps to around 5-11Mbps.

Macbook air wireless also only shows a transmit rate of 5Mbps instead of 150-300 previously on all firmwares lower than .151

Signal strength is reported as very strong regardless - so that's not an issue.

Any ideas as to what could have changed in the latest generation of firmwares (.151 and up, I'm currently on Merlin .162.13) that has all but killed 2.4Ghz performance on 2 devices with different internals altogether ?

This is killing me.

Any help would be greatly appreciated.

Thanks.



Edit:

Changing channel bandwidth modes has no effect. I'm running in N mode exclusively. All other settings are essentially stock. Was getting blistering 2.4Ghz speeds on firmwares below .151. What did Asus change.

 

[thewusman]

So I'm back on .108 and and .112 and 2.4 is perfect but alas no 3G.

 

[owr084]

Have you seen this thread? http://forums.smallnetbuilder.com/showthread.php?t=7303

 

[thewusman]

Have you seen this thread? http://forums.smallnetbuilder.com/showthread.php?t=7303

Um yeah - I posted some observations in that thread.

Bottom line is something has seriously changed in the Asus FW versions circa. 144 and above from my testing.

Some devices simply cannot use 2.4Ghz after updating to those numbers.

Anything before is perfect, and 5Ghz is rock solid on all.

So much pain ...

 

[DaveMishSr]

Hi all

Looking for some advice here.

Disclaimer: I can only get my Huawei E372 3G usb modem working on firmwares above .151 including Merlin's so I'm stuck using the latest releases.

However, on the same range of firmwares my 2.4Ghz performance is basically dead on the following 2 devices:
- 2012 Macbook air
- TP-Link TL-WN822N 300M Wireless High Gain USB Adapter

I use the TP-link as my XBMC windows 7 streaming receiver and the connected rate has fallen from around 240-300Mbps to around 5-11Mbps.

Macbook air wireless also only shows a transmit rate of 5Mbps instead of 150-300 previously on all firmwares lower than .151

Signal strength is reported as very strong regardless - so that's not an issue.

Any ideas as to what could have changed in the latest generation of firmwares (.151 and up, I'm currently on Merlin .162.13) that has all but killed 2.4Ghz performance on 2 devices with different internals altogether ?

This is killing me.

Any help would be greatly appreciated.

Thanks.



Edit:

Changing channel bandwidth modes has no effect. I'm running in N mode exclusively. All other settings are essentially stock. Was getting blistering 2.4Ghz speeds on firmwares below .151. What did Asus change.

That's strange as I am running Merlin's latast release for the RT-N66u and I am getting great performance even with the 5GHz band. I can connect to both bands on my patio so the signal is penetrating 3 interior wall and the exterior wall with a fireplace and built-in barbecue center. Wish I could say why, my channels are set not on auto and bandwidth is set to 20/40MHz, and wireless mode is N only. The only other change I made was to user define QoS so that Xbox live is high and www, tcp, http proxy is highest. I changed the maximum upload bandwidth for Highest to 75% and High to 15% so my sons Xbox 360 would be sure to have enough upload bandwidth to play online games. Other than that all settings are pretty much default.

 

[RMerlin]

Um yeah - I posted some observations in that thread.

Bottom line is something has seriously changed in the Asus FW versions circa. 144 and above from my testing.

Some devices simply cannot use 2.4Ghz after updating to those numbers.

Anything before is perfect, and 5Ghz is rock solid on all.

So much pain ...

Try running this command over telnet or http://192.168.1.1/Main_AdmStatus_Content.asp :

wl interference 4

Does it make any difference?

 

[thewusman]

Try running this command over telnet or http://192.168.1.1/Main_AdmStatus_Content.asp :



Does it make any difference?

Hi Merlin,

Thanks for the advice.

I used OSX Terminal to telnet this command.

Then rebooted.

Initially transmit rate showed 130, then fell back down to 5 again after about 20 seconds as indicated by the screenshot when connected to the 2.4Ghz network

Any ideas what could be causing this from .144 onwards (have tried all your firmwares as well - problem arises from 144.10 and Asus beta .151 and above.)

Anything before that is 100% perfect (but my 3g modem won't connect on earlier firmware builds, so a classic catch 22)

 

[RMerlin]

Do not reboot, or else you will revert the setting I gave you.

Also stick to 20 MHz if you haven't already, that will reduce the chances of interference.

 

[thewusman]

Do not reboot, or else you will revert the setting I gave you.

Also stick to 20 MHz if you haven't already, that will reduce the chances of interference.

Unfortunately no difference / improvement.

Here's the same 2.4Ghz screenshot back on .112 firmware side by side with .162 showing the drop.

As you can see transmit rate shoots back up to 130 (max on 2.4Ghz for the Macbook air it seems).

No settings changed whatsoever - just hopping back to .112 from .162 and vice versa.

Any technical ideas Merlin based on what you've seen inside the firmwares ? Thanks man.

PS:
One observation - the MCS index on 2.4Ghz while on .162 changes to 0. On .112 and lower it is at 15, and is 15 on 5Ghz connections on all firmwares. According this this link http://www.appleinsider.com/articles/11/05/06/mac_os_x_10_7_lion_to_support_450_mbps_wifi_on_2011_thunderbolt_macbook_pro_imacs/ the index of 0 explains the poor speeds. My TP-Link high speed USB adapter exhibits the same problems. So not sure what on the higher firmwares could be causing this behaviour/ result ?

 

[RMerlin]

No idea what MCS index is.

I see you are on channel 5, which is probably not an optimal choice. You should use channels 1, 6 or 11. Any other channel increases the chances of interference, as channel are overlapping.

The wireless driver hasn't changed between 112 and 162, so no idea what would be the problem there. I have no issue here under Windows.

 

[thewusman]

No idea what MCS index is.

I see you are on channel 5, which is probably not an optimal choice. You should use channels 1, 6 or 11. Any other channel increases the chances of interference, as channel are overlapping.

The wireless driver hasn't changed between 112 and 162, so no idea what would be the problem there. I have no issue here under Windows.

I'll keep playing around. Thanks.

Up until an hour ago I didn't know what MCS index was either - but now I understand it's essentially the rate of negotiation / data rates when a link is established on 802.11n networks: http://en.wikipedia.org/wiki/802.11n

For some reason which defies logic on firmwares above .144 the macbook negotiated 2.4Ghz rate is as a good as dead - being 0. 15 would be optimal, which is what it can connect with on firmwares below .144

It's also effecting my TP-link USB adapter running under windows 7, however, only OSX seems to show the MCS index which got me thinking.

 

[thewusman]

"The MCS (Modulation and Coding Scheme) tells the data rate in Mbit/s between the access point (router) and the wifi chip itself. There are values from 0 - 31 which correlates to a specific data rate in conjunction with the used frequency band, coding rate, spatial stream and modulation type.
In this case, higher means better"

So a value of 0 is like being dead in the water.

 

[richto]

No idea what MCS index is.

I see you are on channel 5, which is probably not an optimal choice. You should use channels 1, 6 or 11. Any other channel increases the chances of interference, as channel are overlapping.

That is not correct. Optimal channels in most of the world are 1,5,9,13 and have no overlap (less than 1% interference between access points). Channel 5 is therefore a better choice than 6 in most circumstances.

 

[thewusman]

If anyone has a 2011 or 2012 macbook air and an N66U - would be useful if you could test/confirm your macbook's MCS Index and transmit rate obtained when connected on 2.4Ghz to your router and then confirm router firmware version (either lower than .144 or above).

Thanks

I will aggregate feedback for Asus to look at. Something definitely changed in the router firmware to be causing this - that much I know.

 

[RMerlin]

That is not correct. Optimal channels in most of the world are 1,5,9,13 and have no overlap (less than 1% interference between access points). Channel 5 is therefore a better choice than 6 in most circumstances.

Not in North America, where we only have 11 channels.

 

[Huskypaw]

I'm experiencing the same problem here with my router now. Tried different firmwares & tried an erase of nvram. Tried different devices & different settings - it won't help.

In the first moment it connects with 300Mbps but then in a few seconds it drops down to 11MBps with maximum power and the device right next to the router.

 

[octopus]

There is different with connection speed and transfer speed. Measure transfer speed that is counting.

God place to download drivers: http://www.station-drivers.com/

octopus

 

[RMerlin]

I would take a look at the driver your wireless card is using. If the problem suddenly appeared, then it could be a driver update that was pushed through Windows update, or some other change in your environment (like moving/installing a cordless phone).

In fact if you have a cordless phone that operates in the 2.4 GHz band, you should set your router to 20 MHz max on the 2.4 GHz band.

 

[Huskypaw]

I found out that my Intel 5100 WiFi adapter was a draft n device; after installing a USB stick that was no draft device I can connect with a maximum of 270Mbps - but never 300Mbps no matter how close I am even at 500mW.

I would take a look at the driver your wireless card is using. If the problem suddenly appeared, then it could be a driver update that was pushed through Windows update, or some other change in your environment (like moving/installing a cordless phone).

In fact if you have a cordless phone that operates in the 2.4 GHz band, you should set your router to 20 MHz max on the 2.4 GHz band.

 

[RMerlin]

I found out that my Intel 5100 WiFi adapter was a draft n device; after installing a USB stick that was no draft device I can connect with a maximum of 270Mbps - but never 300Mbps no matter how close I am even at 500mW.

270 Mbps is probably normal.

Did you see if there was a driver update for your Intel 5100?

Another road would be to buy an inexpensive Intel 62xx card, and install that in place of your 5100 Wifi. I upgraded my Asus laptop that way, replacing the Atheros 150 Mbits with an Intel Centrino 6230 (300 Mbits + Bluetooth). Just make sure your laptop would support it (some manufacturers like Lenovo likes to use a BIOS-based whitelist to determine which wifi cards you can install internally).

The Wifi card cost me a whooping 23$ on Amazon.