Hello mosepce
I had the same problem with my G750JX. I found out that it was a loose connector inside the Laptop, this caused my WIFI card to die, unfortunately.
I called my local ASUS support and explained the situation, and they told me to send my laptop in for service so they could fix it.
After I week, I got my laptop back, fully functional.
Here is a link for the ASUS support center in case you need it:
http://www.asus.com/support/Service-Center-All-Countries/Hope this can help you
Regards
TheShwamp
PS: If you send you laptop in for service, make sure you make a backup of all your important files, they may be lost during the service
😉