Alan272

It means that on the motherboard there are 2 sockets for that type of USB that are available for front panel I/o on your case.  It’s a totally different port type than what most people think of as “usb”

If you have a decent card then wait it out. I’m running a rx580 and I’m waiting on ampere 

Up to you really, none of us know your situation

I have the x570 a pro, with a ryzen 3600, with all core overclock to 4.2, I have zero issues. i kinda bought it pretty much as soon as it came out so like a d*ck i did not check the reviews but if i had i would not of bought it, but on the other hand i have had zero issues. only thing that i do not like is the lack of a reset bios option on the i/o, you have to short the pins.

Better than the X570 A-PRO but less than the Asus one.

Yes this it the one and way better than the X570 A-Pro

I have a 2080ti with a 3900x on 850W, you'll be fine...

you'll be totally fine... 650w would have been more than enough for it already
 
and the psu itself is good, so have fun with it i'd say

650w is more than enough.

This is stupid argument IMO, its pretty much the same thermals, the 3800x is just binned better. Also gameplay is going to be mid 60's at most anyway, as you record with Nvidia Shadowplay, or use OBS using Nvenc Encoder, or if you do decide to do CPU encoding it still will be fine

Yes.  Source : I have a 3700x.

Yes. But r7 3800x runs hotter than 3700x so if recording and playing you should consider gettin 3700x or better than stock cooler woth r7 3800x

Try this
https://obsproject.com/forum/resources/nvidia-nvenc-guide.740/

Not needed but preferable. 

no, just can make life easier.

No, you could encode your video/stream on the GPU or CPU

No. You can get enough quality with just bit beefier gaming setup.

if you have roughly a 4th gen intel, 1st gen ryzen with 8+ threads or better, and a 1060 or RX580 or better you likely have good enough hardware to stream most more recent games.  Duel PC is there for professional streamers because it keeps there frame-rates a bit higher, and reduces chances of occasional frame-drops on the viewers end, but if you don't have 100s, or atleast dozens of people consistently watching and donating a duel pc isn't really worth it

I recorded gameplay with both an FX-8150 and a Ryzen 1600x. Using Geforce Experience recording, I never really felt any performance decrease while doing it. 

There are plenty of streamers using one PC. I stream and record games just fine at 720 or 1080p with just a 4c/4t i5 and a GTX 970 blower card. So, you can do O-K on a mid-range sub $700 PC depending on what settings you are using for streaming/recording, the game and the game settings.