After an exhaustive series of tests that has involved 3 routers, 10 different devices, and 3 different USB wireless cards, I have come to the determination that my Alienware Alpha's Intel Wireless 3160 is defective.

Problem : Cannot maintain a reliable connection to any router for more than a few minutes with the Alpha Intel 3160 wireless.

Testing Procedure :
Ping tested to gateway/router with Alpha's Intel 3160 on 3 different routers, at various locations and distances, and the results were always the same -->
After a short period of time, even when signal remains strong, network connectivity always fails and all traffic stops (cannot ping the router/gateway). 

I can move any of the 3 routers tested around, the Alienware Alpha around, and it always happens to where traffic stops and it will no longer ping the gateway/router. 

I have tested 10 other devices (Windows, MAC's, Android devices, wireless G and N, in the same location as the Alpha and done the same ping and IP tests and they all work fine with all 3 of my routers, it is only the Alpha ever loses connectivity to the gateway/router.    I never have any of the other devices even powered on when I try this either, so there is no interference, nor is anything else in my house like a microwave or cordless phone that might be on the same channel.  The card connectivity doesn't always just drop, often times I get 2-3000ms ping response times, often times even when a router is right next to the Alpha, and then shortly afterwards connectivity completely drops and never works again even though signal strength remains in the Wireless-N 120-150mbps range.

However, when I install other USB wireless cards into the Alpha and use those to connect wirelessly, they all work perfectly.  I have installed 3 different USB wireless cards, and I can connect to all of the routers, I can continually ping (ping -t ), and I never lose connectivity of any kind, so this tells me clearly that the Intel Wireless 3160 is the problem, and that it is not something in the operating system.  I have even changed the 3160 to run in ONLY is G and not N, and the problem still persists.

I currently have Intel Wireless 3160 WIFI Driver Version 18.11.0, and I have done a fresh uninstall/install and it has not affected anything.

I just bought my Alienware Alpha too so this is really upsetting as I have not got a chance to use it yet.   I have done some research on the net and around these forums, and the 3160 is apparently a pile of garbage (why is Dell still using these???!!!!??), but this seems worse than anything else anyone has had to deal with.