You can't use remote desktop to project your phone to a PC, especially with continuum support, can you?
With regard to a wireless card, I have a USB wireless adapter.
But wouldn't that take over network usage, which would be much slower than my built in Gigabit?
Where is there some facility where I could do everything else onboard an only use the Wi-Fi for project?
JJ
No, you can't use remote desktop to send your phone to your PC. Sending your desktop PC to your TV (HTPC, or I assume XB1?), phone, laptop or tablet however is best accomplished by remote desktop though (if you have Pro on the desktop PC). Heck, if you have Pro on your laptop it may be a better approach as well. Basically, if you want to control things via the client rather than the server then remote desktop is best. If you want to control it from the server though (so slinging an image onto a screen from your phone, and controlling it from your phone), then Miracast is the way to go. Of course you can't install a Pro SKU of Windows on the phone so that's the only Windows device that is limited. You could put Pro on any other Windows 10 device though, so most things can be made to be flexible. The phone can only be a remote desktop client though. Hopefully the newer more business oriented phones will have a Pro SKU of Windows 10 Mobile available as an upgrade or something, Surface Phone? Amusingly, you can use remote desktop to project and control your Pro desktop PC on your phone. That's one powerful phone. Watch your friends look on in astonishment as you run full gaming rig power on your phone. Don't tell them about the PC upstairs...
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Yes, using Miracast in the method described here could mean that your wifi stick would take on the internet and general networking duties when connected. This can be addressed, with different things redirected through different cards, but that is not commonly done or easy to explain. Of course, you could make a direct Miracast link to a device via the wifi stick (by connecting it to a wifi device like a Roku stick instead of the router, possibly a PC can be configured to act in this manner?) and use the wired card to connect to the internet, that might be a bit of a bind but will probably work without issue. Time to experiment. There is no inherent reason why you can't use two network adapters at once for two different things, you just need to muck about a bit to make sure it's doing what you want.
Think about what you need to do, the bandwidth you need, the latency considerations, and choose your networking components based on need. How fast is your internet connection? I have a 200Mbps connection, so this matters to a degree but does one device need all of that at any given time? What wifi reception do you get? Take your wifi link speed as reported by your PC and halve that, which should give you an idea of throughput in reality (test for best info). If that is better than your internet speed (quite possible if your have ADSL or ADSL2+ or the cable equiv.) then you should be good. remember other devices can use that wifi bandwidth if they use the same frequency to the router.
Networking is a big topic. Wifi doubly so. Beyond Miracast, if you want to learn about networking you'll need to read a lot and play around with it.
Good luck with that wifi stick. It probably does not support Miracast, but it might. Of course, the ideal would be to find an NDIS 6.4 compatible wired Ethernet card, I wish I knew one that did this as I'm sure there must be one. Will you let us all know how the USB stick fared by posting after you've tried it? If so, let us know the make and model.