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New RT-AC66R slow 5ghz connection

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Hi all, I just bought an RT-AC66R from best buy to replace a netgear wndr4500 I had been using. I hooked it all up and configured and I'm getting some extremely slow speeds on the 5ghz band. My pc with wireless card is about 20 feet away across room with no major obstructions. My Internet connection is 100Mb down and I actually get close to 120Mb on most days. Doing speedtests on my old wndr4500 I would get every bit of that 120Mb on the 5ghz band. On the new AC66 I'm getting 20Mb at most. And the download graph is really jumpy. Just a lot of dips. Settings for the 5ghz band are channel 161 and 80mhz bandwidth. Encryption is wpa2-personal. I have the 2.4ghz channel off as I don't need it. On inssider my signal strength to the PC is -43dB. Any ideas on why this is so slow on the 5ghz band? Thanks!
 
First of all check what firmware you have installed in the router.
You can search for a stable f/w here in the forum. Are you using a cat5e/cat6 cable on the Wan-connection ?
I am using lower band than 161 on the 5 GHz band and 40 MHz bandwidth.


Hi all, I just bought an RT-AC66R from best buy to replace a netgear wndr4500 I had been using. I hooked it all up and configured and I'm getting some extremely slow speeds on the 5ghz band. My pc with wireless card is about 20 feet away across room with no major obstructions. My Internet connection is 100Mb down and I actually get close to 120Mb on most days. Doing speedtests on my old wndr4500 I would get every bit of that 120Mb on the 5ghz band. On the new AC66 I'm getting 20Mb at most. And the download graph is really jumpy. Just a lot of dips. Settings for the 5ghz band are channel 161 and 80mhz bandwidth. Encryption is wpa2-personal. I have the 2.4ghz channel off as I don't need it. On inssider my signal strength to the PC is -43dB. Any ideas on why this is so slow on the 5ghz band? Thanks!
 
Firmware is 3.0.0.4.270

I did try the 40mhz and some lower channels and its even slower. I am using cat 6 on the wan. I hooked up a long cat 6 cable to my pc and one of the LAN ports and its hitting the 120mb mark. It's just the wireless 5ghz that is extremely slow on my pc and ipad.
 
You could try a factory reset and set your current settings again.
If no improvements on the 5GHz bnamd try a clear nvram and set your settings again and seeif is solves the issue.
I am running Merlins firmware 28.Beta1.

Firmware is 3.0.0.4.270

I did try the 40mhz and some lower channels and its even slower. I am using cat 6 on the wan. I hooked up a long cat 6 cable to my pc and one of the LAN ports and its hitting the 120mb mark. It's just the wireless 5ghz that is extremely slow on my pc and ipad.
 
This is going to sound crazy, but bear with me...

I had a similar situation to you but I swapped out a WNDR3700 for a RT66R - I had exactly the same performance issues and it turned out to be client related. I dont exactly understand the logic of how the WPA/AES could be different on a Netgear vs ASUS, but I could see large numbers of DHCP requests from the same clients in the ASUS log (you will have to enable DHCP logging in the UI). Bottom line is I assumed that just creating a new network with the same SSID and WPA/AES setup, and swapping the routers would do the job - it may be very client specific, but I also had to 'reestablish' the WIFI setup on each for it to correct the issue.

Now this may be very specific to the clients I am using but you can easily prove it - temporarily change the SSID to something new so nothing existing connects to it, and choose a single client to connect to this SSID. If it works and there are no issues then you can add the existing clients one at a time and monitor it. If there is an issue with just a single client then you can check the firmware versions as already mentioned and try and figure out what is happening.

I personally am running the latest Merlin beta (http://forums.smallnetbuilder.com/showthread.php?t=7846) , and I get significantly greater range on both 5 and 2.4Ghz compared to the 3700 - but the swap-over wasnt as straight forward as I expected due the clients rather than the router.

p.s. despite mixed results from other people, I am running 20/40/80 with auto channel for the 5Ghz with no issues at all.
 
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This is going to sound crazy, but bear with me...

I had a similar situation to you but I swapped out a WNDR3700 for a RT66R - I had exactly the same performance issues and it turned out to be client related. I dont exactly understand the logic of how the WPA/AES could be different on a Netgear vs ASUS, but I could see large numbers of DHCP requests from the same clients in the ASUS log (you will have to enable DHCP logging in the UI). Bottom line is I assumed that just creating a new network with the same SSID and WPA/AES setup, and swapping the routers would do the job - it may be very client specific, but I also had to 'reestablish' the WIFI setup on each for it to correct the issue.

Now this may be very specific to the clients I am using but you can easily prove it - temporarily change the SSID to something new so nothing existing connects to it, and choose a single client to connect to this SSID. If it works and there are no issues then you can add the existing clients one at a time and monitor it. If there is an issue with just a single client then you can check the firmware versions as already mentioned and try and figure out what is happening.

I personally am running the latest Merlin beta (http://forums.smallnetbuilder.com/showthread.php?t=7846) , and I get significantly greater range on both 5 and 2.4Ghz compared to the 3700 - but the swap-over wasnt as straight forward as I expected due the clients rather than the router.

p.s. despite mixed results from other people, I am running 20/40/80 with auto channel for the 5Ghz with no issues at all.

Bro, you are a God among men. I changed the SSID and it is blazing now. Thank you very much. So you do recommend the Merlin beta? I might have to try that out sometime. I have another question on the regular firmware. Does it help to increase the default power from 80? If so what do you all recommend the maximum that it be set, too? I really appreciate your all's help!

p.s. do you find that you get better speeds with it set to 20/40/80 and the channel to auto? I always thought the highest MHz and highest channel(161) always gave the best performance, but I admit I am not an expert on this stuff.
 
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Well I turned the power level up to 100 mad it actually slowed my speeds down again. That doesn't seem right. Also, I find I have to change the SSID every time i change a setting and save or the speeds drop again. This thing is finicky. Does it still have these same issues with the Merlin firmware?
 
Bro, you are a God among men. I changed the SSID and it is blazing now. Thank you very much. So you do recommend the Merlin beta? I might have to try that out sometime. I have another question on the regular firmware. Does it help to increase the default power from 80? If so what do you all recommend the maximum that it be set, too? I really appreciate your all's help!

p.s. do you find that you get better speeds with it set to 20/40/80 and the channel to auto? I always thought the highest MHz and highest channel(161) always gave the best performance, but I admit I am not an expert on this stuff.

LOL - Glad to be of help, but I think this pretty much underlines what I saw - the radio firmware is not as good at dealing with 'chatty' clients.
I have theory that the ISKAMP key rotation is different or has something slightly different in it between vendors , so the effect is that the client that connected fine to the Netgear, can only partially negotiate the WPA2/AES connection phase and then it falls back and retries. The repeated connect / disconnect / connect / disconnect is 'swamping' the radio and basically preventing it serving real traffic (I hasten to add this is my *theory*, not sure if Thiggins drops by this thread, if he has any thoughts).

Anways, I can tell you 20/40/80 should appropriate the best setup for your local environment - although yes, the higher channels do give the best performance but it is very environmental, depending on what other wireless networks and interference are in the area (should be minimal interference with 5ghz compared to 2ghz).

In my experience you have to watch increasing the power as it will also increase the SNR ratio and as you saw reduce the throughput in some cases - I have read other threads where people actually get better throughput by lowering the TX power (using DD-WRT people reported 71mw gave the best results). Personally I get the best results with both radios at 100mw, but then again most of my clients are a fair distance away. (100mw is a number I came up with as comparable to the old Apple Airport devices I used to use in conjunction with the WNDR3700)

I would strongly recommend the merlin beta, because it is essentially the ASUS firmware with some code and feature corrections that Merlin has made (often with input and review from ASUS themselves). Its not a 3rd party build as with DD-WRT, but is just a 'patched ASUS' build.

Right now the beta (v3.0.0.4.354.29) has the next-generation wireless drivers (warning: they are in beta) so you don't get the 100% uptime, but I do get significantly better stability on my 5Ghz.
If you want to play it safe then run the (3.0.0.4.270.26b) with the older drivers, as they have fewer issues with different clients.
I should say the beta runs fine with all my clients, but you might just have to try it and see in your own setup.
When you switch between builds I would always recommend a factory default reset - just to make sure you are always using the correct NVRAM variables.

As a final note on the clients, I dont know of any easy way to remove the wireless profiles easily - a lot of my clients are embedded (dropcam HD , printers etc) which means the only real way to be sure is to manually re-setup the wireless profile on each one (hence the new SSID gives you a point of reference). Personally I prefer this anyway as after every client i add, I re-run the speedtest - and it if dies, then I have a pretty good idea of which one is causing the issue.
 
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