Why the extreme difference in performance on same 801.11 AC connection

I have three systems on 802.11ac all using ASUS Wifi adapters, plus an 802.11 ac TP-Link Archer C9 router. I use only the 5.0 GHz band for all my WiFi operations.

I have a desktop where I keep the Wifi antenna on the edge of my desk. I position my laptop maybe a foot away from the desktop WiFi antenna. I have this file synchronization utility, GoodSync, which reports file transfer speeds. Here is the thing. Sometimes GoodSync reports file transfer speeds at 18-20 MB/sec. Other times, that speed is done to 2 MB/sec or even less. Rebooting both desktop and laptop does not fix the problem of slow transfer rates.

So what is causing this huge difference in performance? How can I set things up to always have 20 MB/sec transfer rates?

I keep the space between desktop antenna and laptop free and clear. No metal, not even any paper.

Thanks,

x509

Couple questions...are you surrounded by neighbors using the same channels? How far is the router from a wireless phone base? Is QOS on in your router, if so turn it off.

dmholt57 said:

Couple questions...are you surrounded by neighbors using the same channels? How far is the router from a wireless phone base? Is QOS on in your router, if so turn it off.

Not sure about the neighbors. The router is about 30 feet from the wireless phone base. But the phone is maybe 10 years old, so I'm sure it is on the 2.4 GHz band, and I'm operating only on the 5.0 band. If it matters I have the 5.0 GHz band set to Channel 44.

My router is a TP-Link Archer_C9, and I couldn't find a QOS setting.