Seamless way to setup a second streaming PC

First things first, hardware setup. To have everything plugged in correctly, allows us to continue with the software setup.

Requirements:

1. 1x 3.5mm aux splitter.
2. A double ended male-to-male aux cable.
   
3. A streaming PC with an ethernet connection - even better two (1 for direct communication to the main PC, and the other for hosting the stream).
   
4. A gaming PC with preferably two ethernet ports (same reason, but one is for hosting general internet access).
5. An easy webcam connection via USB (if your streaming PC is across the room like mine, use a USB extender. You can pick them up for a few pounds).
6. And general streaming PC requirements; like a low-tier GPU, fair amount of RAM, and a decent CPU.
7. An extra HDMI (a long one, if your streaming PC is across the room) to compliment your existing monitor connections.

Apart for PC hardware, this shouldn't really cost anything more than £20 for the extra cable hardware!

Hardware setup
By continuing, I am going to assume you've turned on your streaming PC, and turned on your main PC.

• Firstly, without touching existing connections to your main monitors, grab an extra HDMI cable and plug it into the capture card (HDMI IN) from your main PC's GPU (HDMI OUT).
• Get a suitable length ethernet cable and plug it in from one PC to the other. If not, just use your LAN.
• Plug an ethernet cable from your streaming PC to your router. This is vital, as using a cable provides the most reliable connection and consistent speeds. WiFi is an option, but it puts you at risk from giving your viewers a bad time.
• Use a 3.5mm aux splitter and replace your existing audio output with it.
• Plug your speakers (that you unplugged for the splitter) and plug them into the splitter.
• Use a double ended aux cable, and plug it into the other half of the splitter.
• Then, plug the other end of the aux cable into a microphone input on your PC. Make sure you still have your main mic connected. If you don't have space, I can't suggest anything and this may not work out for you.

And you're set up!

Right, video should all be sorted by default. You've plugged the HDMI from your main PC to the HDMI in on the capture card of your second PC but what about the best way to configure the video and audio? How are we going to speak to our friends, and play games on our MAIN PC while having it all mirrored to the streaming PC?

Originally, I thought it was a great idea to use the HDMI OUT of the capture card and plug that into my monitor. But this is hands down the worst way to approach it.

• It adds noticeable input lag.
• It caps you to 60fps on high-refresh rate monitors (unless you have the 4K60 Pro).
  
• Image fidelity is slightly compromised.

You'd think "let's set the HDMI audio output as our main audio device, then plug our headphones into the monitor as an audio output while capturing it at the same time" but it's just really awkward and gives you issues that contradicts the whole point of using a second streaming PC in the first place. AND if you turn off your streaming PC connections to the monitor are gone and you'll need to re-route the cables or turn on the streaming PC. Ugh.

Se let's do it differently:

• Keep your existing monitor connections the same, and (as I said before) add your third HDMI connection to the capture card. Your PC will recognize this and assume you've added another monitor.
• Go to the Windows display settings (right click the desktop), and mirror your primary gaming monitor with the third display (the capture card) instead of having the display extended. This should be simple enough to not go into detail.
  
• Now it should look something like this:
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• So anything you do on your gaming display will be identical to that of the video signal sent through the HDMI to your capture card.

Unfortunately, this removes all audio to the capture card but your monitor has a native video input! Games will feel and play exactly like they will when you don't stream, but you've also mirrored your gaming display to the second PC too.

So... about the audio...
It's no tricky task!

• Where you used the splitter to split the audio to your speakers and through a double ended aux cable to a mic port, go to the recording devices section of Windows.
• You can do this by right clicking the audio in your taskbar, and selecting "Recording Devices".
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• In the recording devices, click the "Recording" tab.
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• Find the mic input you split your desktop audio to. Play a YouTube video, and see which mic input is active in correspondence to the video you're playing.
• Right click the device, and select "Properties".
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• Click the "Listen" tab at the top.
• Check the box that says "Listen to this device"
• And then find the HDMI output on your graphics card. If you're using an Elgato it's labelled "elgato (Nvidia high definition audio)".
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• Doing this means that not only is the splitter you use giving you native desktop audio to your speakers or headphones, but it's also looping that same audio output to a mic port, that is then re-routed through the HDMI from the graphics card to the capture card of your second PC.

Bam! desktop audio is now sorted. Mic audio... not so much.
The idea with mic audio, is that we want to keep it separate so that we can apply voice specific features and filters for a better quality stream without affecting game audio. And this is something we will have to do later on.

Controlling your streaming PC without using another monitor
Ok, using the HDMI output of your streaming PC's GPU to a monitor to control is IS always an option. And doing it that way voids my technique of getting mic audio across. There is a much easier way to do it - Remote Desktop.

Remote Desktop is a built-in feature of any Windows OS. You have it, and in this case, it's very useful. Almost all companies use remote desktop for if they have Windows servers, as technicians can control servers from their home.

So, temporarily plug your streaming PC into a monitor, grab a spare mouse and keyboard and let's get it workin'.
In your streaming PC...

• Go to your Control Panel > System and Security > System > (left side) Remote Settings
• When a new windows appears, check the box that says "Allow remote connections to this computer" and nothing more.
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• Press OK.

Right, so now our streaming PC is open for remote connection! Now you can find the local IP by going into the command prompt, typing "ipconfig" and using the local IP to remote connect but there is a better, more memorable way of connecting which we will do later on.

Anyway, everything aside, we have remote connection! You're not far from disconnecting your temporary display and using the remote connection as means of interacting with your streaming PC.

Sharing internet, and local files between both PC's
This is another insanely useful tip - using a local network for file transfers.
What we're going to do, is allow the streaming PC to share files with a direct ethernet connection between both. Like... one end of the ethernet between both PC's.

If you don't have enough ethernet ports to spare you can either use a network switch, or use your router's LAN.

But other than that, let's get into the setup:
On your main PC...

• Go to the Control Panel > Network and Internet > Network and Sharing Centre.
• In this area, find the medium in which you use to access the internet be it a WiFi adapter or ethernet cable (displayed on the right).
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• Left click on the device you use to connect to the internet.
• A "WiFi status" window should open.
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• Click "Properties".
• Click the "Sharing" tab at the top
• And check the box that says "Allow other network users to connect through this computer's internet connection".
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• This, as it says plainly, means that any internet connections you have to your main PC can be shared to the streaming PC.
• Yes, this also means you can plug an ethernet cable to your main PC, and then through a second LAN port on your main PC share the internet to the streaming PC!
• This means we've given our streaming PC access to the LAN, which by default, creates a direct connection through the ethernet cable which we can take huge advantage of.
  
• But we're not done. We need to tell windows which ports to open between the shared connection. Especially port 3389 and 80 which is the remote desktop port and HTTP port!
• So click the "Settings..." button.
• And tick all the boxes for full access (which includes the necessary ports for remote desktop and web browsing)
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• Press OK.

And you're done!
You've not only opened the option to share the internet to the streaming PC through your own, BUT you've also opened the option for a remote desktop session through 1 ethernet cable bridged between both computers. This ensures ultimate reliability, and super fast file access without the use of your router.
If you can't spare any extra ethernet ports, don't worry there are options. All we've done here is allow a direct connection. Using a LAN doesn't require this setup! Just make sure your PC is open to discovery through your local network.

File access?
So how do we share files seamlessly between both computers?
And, before we start, I want to let you know that this is also an easy way to remote connect to your streaming PC (without memorizing an IP!)
On your main PC...

• Go to your file explorer.
  
• On the left should be "Network" under your main storage drives.
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• Your streaming computer should be listed there with an obscure name.
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• By double clicking it, you will be denied access to the computer's files. Let's fix that.
• Right click it, and select "Connect with Remote Desktop Connection"
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• Aaaaand now this is where you realize you are now controlling your streaming PC from the same keyboard and mouse as your main one. This also means it's acceptable to just disconnect the extra display and spare kb/m you used for the streaming PC's setup.
• Now you're connected to your streaming PC remotely, go to "This PC" in the file explorer.
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• Right click your streaming computer's main drive (probably drive C:)
• Select "Give access to" > "Advanced sharing..."
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• In the Window that pops up, select the drive you want to share. For most people their main drive is C:.
• Then click "Permissions"
• And near the bottom where is says "Permissions for Everyone" check the box that says "Full Control".
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• Press OK.

Now, you can go back to your main PC, go to "Network" in your file explorer, double click your streaming PC, and have complete control over ALL files and folders. And, because this is done through a direct connection via ethernet, files can be transferred, deleted, copied and moved with gigabit speeds.

Ok... mic audio
Ah yes, back to audio. Right, so again, the idea is that we want to keep the mic audio seperate to the desktop audio. We COULD use the "Listen to this device" feature we used for desktop audio but we're not! Luckily for us, not only can we receive video data from the remote desktop, but we can ask it to stream our mic to the remote computer too!

• In your main PC search for "Remote Desktop Connection"
• Select "Remote Desktop Connection"
• DON'T HIT CONNECT!
• There should be an arrow with "Show Options" next to it - click it.
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• Click the "Local Resources" tab.
• Under "Configure remote audio settings." click "Settings..."
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• Under "Remote audio recording" check the box that says "Record from this computer".
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• Press OK.

The mic streamed is the default mic of your main PC. Make sure your main mic is set to default!
So, when you next remote desktop into your streaming PC you'll have HDMI audio to the capture card AND a seperate audio device called "Remote Audio" which is also being streamed over the ethernet cable to your streaming PC.
Below is a screenshot of the device being shown through our streaming PC: