Why did the Internet speed drop on Asus RT-N66U?

Question

ASUS

I bought an Asus VivoBook S400CA laptop a month ago (with Windows 8 on board), set everything up and worked fine on it. I connected to the Asus RT-N66U router and the speed was 60 Mbps (exactly, as in the tariff plan). But a couple of days ago, after updating the Asus RT-N66U firmware (latest firmware 3.0.0.4.374.979), the speed dropped to 2-3 Mbps. At first I sinned at the provider, but then I connected via a smartphone and a tablet and both worked at 50-60 Mbps.
I thought that something was wrong with the firmware. I rolled back to the previous version - nothing helped. Reset to factory settings - nothing.
Then I thought about the drivers on the laptop, updated it, made rollbacks, reset the whole laptop to hell with the factory settings - and still it does not raise the speed above 3 Mbps.
PS I'm sitting right next to the router and the connection quality is excellent. It's strange, but the ping is 10-12 ms on both the laptop and the phone, and the speed is different. I check through speedtest.net and 2ip.ru.
PPS The laptop is Qualcomm Atheros AR9485WB-EG.

Answer 1

Disable software "from the manufacturer". The problem is probably in it, tk. not the first time already on asus similar problems with the network

Answer 2

Try to exclude 802.11n mode in wi-fi settings. How is the wire work?

Answer 3

Managed to do it? I have the same problem with this asus?