ASUS USB-AC56 & PCE-AC68 Dual-Band Wireless AC Adapters Review
Oftentimes, I have friends that ask me to help them fix their wireless networks. On more than one occasion, they only have one or two computers in their home, so there really is no reason for the network to be slow due to saturation. What I often discover is that they either are a victim of interference in the 2.4GHz wireless spectrum, or they have a low quality/damaged wireless adapter. With laptops, it is usually more of an issue of a low quality adapter because all the major players put cheap network cards in their machines. Other times, especially with desktops and USB adapters, they are simply damaged, which usually involve a bent USB connector.
via ASUS USB-AC56 & PCE-AC68 Dual-Band Wireless AC Adapters Review.