RT-AC87U very poor performance

[Fatbloke]

Hi All

I am new to the forum. I hope someone can help.

I have an RT-AC87U router connected to my virgin media modem on a 200mb broadband connection.
Hard wired, I can occasionally get around 200mb download speed. With wi-fi it is around 30 - 45mb and is not a smooth download. It also drops the connection sometimes although all devices get a pretty good signal strength.
I had a look on the web for some info on this. I tried with QOS on manual and auto and also disabled but bandwidth is still around 30 - 45mb.
It has the latest firmware installed.
I cannot get reasonable performance out of it.
What can I do to fix this?

Cheers

 

[ColinTaylor]

Have you put the virgin media superhub in "modem only" mode?

What kind of wireless speed were you getting without the Asus and connecting directly to the superhub in "wireless router" mode.

 

[Fatbloke]

Have to put the virgin media superhub in "modem only" mode?

What kind of wireless speed were you getting without the Asus and connecting directly to the superhub in "wireless router" mode.

Yes the superhub is set to modem mode. I will need to test the speeds with the superhub. It kept dropping connections a while ago so I put the Asus in. The connections were more stable but occasionally I need to disconnect and reconnect wi-fi devices as the internet browsing just hangs up. Web browsing is normally very laggy and speed tests are low. I have read a few posts on this site and it seems I need to do a factory reset and reconfigure after a firmware update. The router has always had these issues so it's not the firmware update that has caused them. I will try the reset first and see how things go.

Thanks for the response.

 

[ColinTaylor]

I don't know whether it applies to your router/firmware but Merlin has said that there's "issues" with Asus' beamforming implementation (Wireless - Professional) so try turning both of those off for 2.4 and 5GHZ. Also try disabling Airtime Fairness as that's another potential problem.

 

[Fatbloke]

I don't know whether it applies to your router/firmware but Merlin has said that there's "issues" with Asus' beamforming implementation (Wireless - Professional) so try turning both of those off for 2.4 and 5GHZ. Also try disabling Airtime Fairness as that's another potential problem.

Thanks, I have just tried these and there's no real difference. If anything the download test was more erratic and slow getting up to the approx 45mb speed.

 

[joegreat]

To debug throughput issues on LAN or WLAN you need to follow a more 'scientific' approach:
1) rest your router to Factory Defaults (via GUI)
2) do an absolute minimal config to allow LAN/WLAN to work
2a) do not use any advanced features like AiProtection, Adaptive QOS, etc.
3) test the performance
4) continue step by step to do the further config of the router and test the performance after each step - here you will find out the setting in question
4a) a reboot (with power down!) after each config change is recommended to have always the same starting point for the test!

With this approach you can find out if any config issue is slowing down your router...

By the way: What is the type of cable between the router WAN port and the cable modem?
It should be at least CAT 5E (or better) - otherwise you can get also the slow network performance you experience...

 

[Fatbloke]

To debug throughput issues on LAN or WLAN you need to follow a more 'scientific' approach:
1) rest your router to Factory Defaults (via GUI)
2) do an absolute minimal config to allow LAN/WLAN to work
2a) do not use any advanced features like AiProtection, Adaptive QOS, etc.
3) test the performance
4) continue step by step to do the further config of the router and test the performance after each step - here you will find out the setting in question
4a) a reboot (with power down!) after each config change is recommended to have always the same starting point for the test!

With this approach you can find out if any config issue is slowing down your router...

By the way: What is the type of cable between the router WAN port and the cable modem?
It should be at least CAT 5E (or better) - otherwise you can get also the slow network performance you experience...

Thanks, I will try and do a reset soon and do some testing. It's cat 5e cables throughout the house (probably each less than 50m) so it will be minimum cat 5e for the WAN cable but it may be cat 6.

 

[ColinTaylor]

By the way: What is the type of cable between the router WAN port and the cable modem?
It should be at least CAT 5E (or better) - otherwise you can get also the slow network performance you experience...

My understanding is that the problem only effects Wi-Fi and not wired connections.

 

[Fatbloke]

Hi All

I checked the wired speed and it was around 60 MB also.

I have now done the router reset and reconfigured it with basic config.

I now get 220 whilst wired but the WiFi performance is still very poor ranging from 13mb to 60mb. It seems to have settled down to around 50mb - 60mb.

I have used several different web based speed checkers and they are all around the same values. 220mb wired and 50mb - 60mb wireless.

Downloads do seem slightly less erratic.

QOS is disabled.
DHCP server is disabled as I have a windows DHCP server connected.

I tried disabling the beamforming but it dropped to 13mb. I have enabled it again and it has settled to the figures above.

Any other ideas?

Dave

 

[joegreat]

Which client are you using to test the wireless throughput? Only newer AC enabled clients (e.g. SmartPhones) will give you the same throughput as your LAN/WAN speeds show.

My AC87U setup gives me full WAN throughput (150 Mbit) on newer devices (e.g. iPhone 6s or OnePlus 3T) but only 60 Mbit on older Samsung Galaxy S.

 

[Fatbloke]

Which client are you using to test the wireless throughput? Only newer AC enabled clients (e.g. SmartPhones) will give you the same throughput as your LAN/WAN speeds show.

My AC87U setup gives me full WAN throughput (150 Mbit) on newer devices (e.g. iPhone 6s or OnePlus 3T) but only 60 Mbit on older Samsung Galaxy S.

I used to get over 200mb on my AC laptop but it's also around 60mb now. The main issue is that there is a lot of lag between pages and the download / scrolling is erratic. The other clients are relatively new smart phones but there is also older tablets.

 

[Luboknok]

Ditto, AC87u is fast on boot (70mbps) but gets slow after a couple days. Latest Merlin running Openvpn on it. Older OCed 68u was faster by 20% and ran cooler. Reboot and it works ok (35mbps VPN) for a couple days.