Open Broadcaster Software is a great tool for live streaming, but sometimes it can be a bit of a CPU hog. Here's a quick cheat sheet for squeezing every last drop of performance out of your computer.
Get a dedicated capture card - nothing reduces CPU use like dedicated hardware. A dedicated capture card is the way to go.
Don't scale your output - scaled output is great if you want to balance your CPU use and your bandwidth use, but scaled output takes a ton of CPU power. Make sure that whatever resolution you're capturing at is the same as the resolution you're streaming at and don't scale your output.
Use a lower bitrate - while this will directly affect the quality of your stream, a lower bitrate will help you use less bandwidth and, importantly, have less CPU overhead (and also a lowered use in memory).
Set your CPU Preset to veryfast or ultrafast - this one seems like a no-brainer but a lot of people forget about it.
When in doubt, capture at a reduced resolution - if all else has failed, lowering the resolution of what you're capturing down a notch can always help reduce the CPU use. Instead of playing at 1920x1080, play at 1280x720, and capture that instead.
Remember: when it comes to CPU use less is more.
In this video I discuss what webcam would work best for live streaming, given a limited budget.
The Logitech C950 is a great deal for a 1080p USB 3 webcam. At under $100 it won't break the bank for the entry-level streamer.
Most importantly, it looks really great.
You can either use OBS Studio Browser Plugin (this is NOT CLR Browser), or do a screen capture!
Either way you're going to need to fiddle with it to make it work right.
Short answer: no. Long answer: maybe.
YouTube's recommended encoding settings really boil down to two things: bitrate and framerate. Everything is basically industry standard.
YouTube supports a wide variety of framerates, and recommends you use the same framerate as your source video to encode with - that's the great news. The bad news is that if you're recording in an interlaced format (for example, 1080i60) you'll need to encode it in a progressive format at half the framerate.
The other end of the equation - the bitrate - is a little more of a touchy, subjective thing. For some videos 10Mbps at 1080p60 will work just fine. Other videos will look like crap because of the content. It's really up to you to decide just how much bandwidth you're going to dedicated to your video; but, for the average video, 15Mbps at 1080p60 should be enough to look good.
I done took it apart.
The Magewell HDMI to USB 3.0 dongle is a cool little device that lets you capture 1080p60 footage through an HDMI connection. While this little device does serve its purpose well, it has some design flaws that keep it from being really spectacular.
The biggest flaw of this product is its physical design: after repeated use the USB and HDMi ports are starting to come loose, and the unit itself gets extremely hot to the touch, to the point of burning - creating serious internal thermal issues.
The case of the Magewell acts as the units heatsink, and if it is buried in a rack or behind a computer it's going to overheat and fail.
I'd recommend other USB units for HDMI capture for the average person as $300 is just a wee bit too much to spend on a product that's going to suffer from some design issues.