Review on TP-Link AC1900 USB WiFi Adapter (Archer T9UH) - Dual Band Wireless Network Dongle for Desktop with High Gain Antennas, Supports Windows 10/8.1/8/7, Mac OS by Dustin Miller

5 stars. This is a replacement for a simple plug-in wireless N adapter. We couldn't stream 4K movies on our home network, so we decided to give it a try. Installation was easy. You either plug it directly into a port on your computer, or you use a mount to insert it and run a cable from the port to the mount. Because this particular computer only had 3.0 ports on the front and not the back, we decided to use a stand instead of sticking out the front of the computer. It looks great in a stand, giving it more height than when connected to a computer placed on the floor, so that's not a problem. The disc that came with it didn't work at all with 10x64. It just kept throwing errors. Going online and downloading the correct drivers was easy enough and they installed without any problems. It connected to the network with no problems. One thing I don't quite understand is how it chooses the type of wireless network it uses. For example, when I first installed it just 4 hours ago it stayed in the 2.4GHz band for about an hour and when I went back and checked again it was in the 5GHz band. The box says you can choose between two strips, but it doesn't say how and there are no instructions. So I hope it stays in the 5GHz band because I don't know how to change it if it doesn't work. Also, there are no instructions on how to change the channel used. Of course, this only applies to people who don't yet know how to do something like this, but there are many of them. Me included when trying to install this on Windows 10 on a friend's computer. I don't know where everything is in Windows 10 so a basic guide would be helpful. Another thing is the antenna. It doesn't tell you how to place the adapter in the desired direction for optimal coverage. I know it's omnidirectional so it's probably not a big deal. It just seems that one way is still slightly better than the other. But on top of that I tried to stream 4k movies to 2 different places in the house which didn't work before. They both streamed with no buffering! For now, this device seems to have solved my problem. I would recommend this device. If anything changes I will come back and edit this review. EDIT 1 Star: This product only worked for about 10 days before the speed just dropped. Worked great for the first 10 days. I was able to stream whatever I wanted with no buffering issues, so I got this device to upgrade from the Wireless N adapter built into my computer. For some reason I still don't know why, after about 10 days it just went in the trash. I can't stream 4k, Bluray or even DVD quality on a 1.3GB home network, not over the internet. It says it's over wifi in a 1, 3 Gbps network is connected, but the connection appears to be dead. I can't stream anything from my home network to another device in the house. On the web, speed tests only get around 20MB, whereas they used to get my usual 150MB. If I unplug this device and go back to the PC's built-in Wireless N adapter, the internet speed will be what it should be and I can stream DVD and Bluray quality on my home network but still not 4K so I have bought that. I wish I knew what happened to him so I could fix it. All I needed was a little extra speed so I could stream 4K on my home network, it worked great for 10 days, but then something happened and now it's much worse than my Wireless N connection. I have erased the device, reinstalled, disconnected from network, reconnected several times, restarted PC several times. Nothing works. Looks like I'll be returning it for a refund and trying to find another wireless power adapter. EDIT #2 3 Stars: After playing around with this for a few days, something made me think about trying a system restore. So I restored the PC before I installed this adapter for the first time. After the restore I reinstalled this adapter and in fact it works great. My internet speed is where it should be. I can DVD Stream Bluray and 4K movies over my home network without buffering. It works just as well as it did when it was first installed. Should I keep it now or return it because it is untrustworthy? I still have about 2 weeks to get it back so I will be using it for at least a week. If it goes wrong even once, it will come again. Edit #3 3 Stars: Well I have 5 days left to return it and it got really messed up today but that's not the adapter's fault. At least I don't think so. Windows performed an update and then reset all network settings to their default values. It messed everything up, but after I put the settings back to where they should be, everything started working again. It's not really the adapter's fault, so I won't blame it. However, one thing I noticed that is a bit annoying is how the adapter connects after a reboot. On reboot, the adapter shows it's using the Wireless AC protocol, but it runs on the 2.4GHz band and on a low channel, 3 for me, for about 10 minutes. After about 10 minutes, it switches to the 5GHz band and a higher channel that hits the hundreds. So for me the internet is very slow and video streaming on my home network is completely disabled until it gets into the 5GHz band. I don't know, why doesn't it connect to that band instead of the 2.4GHz band? I will reluctantly leave it simply because when it works it works very well.