For months I was getting low internet speed on my Linux box which is a Ryzen build with Asus a320m-k mobo. I was using a rt5372 adapter connected via USB and my internet speed wasn't getting more throughput than 8Mb/s.
When I booted the same Linux distro with my laptop with no internal wi-fi card I didn't experience the same problem. Speedtest was merrily showing 30/40 Mbit/secs. That got me to thinking. Because this meant:
- Wifi Module
were working okay. And the problems people experienced with the
rt2800usb didn't apply to me. Or at least to this scenario. The problem was somewhere within my own box. Updating to the latest BIOS, to my disappointment, didn't solve my problem. I thought "maybe some obscure bios setting is borking it" and decided to take a gander to the manual.
When I was looking at it a lightbulb appeared in my mind on the part where it shows the backward panel connectors:
I was plugging my dongle to the part where it says 4, which meant USB 2.0. My laptop was using USB 3.0 all the way so that was the only difference. It turns out that if you connect your dongle to a USB 2.0 port it gives you poor performance on wifi - I have no idea why Windows can work with 2.0 but Linux can't. This even solved the annoying problem of "I can see and connect to all the wifi networks except yours, master!"
So long story short, in case you are experiencing a speed problem with your usb dongle on Linux but not in windows, use USB 3.0 (blue ports) and try again.