Tundral

HDMI 1.4b does support 120hz@1080p!

Just install Ubuntu or Pop-OS or something on one of the drives. The process is really similar. Then install graphics drivers and Steam (Pop-OS should have an 'app store' you can easily get them from). With Steam you could just download and try out some game (preferably one you have issues with) that's compatible with Linux and see if you have the issues you do with a Windows install.

You do mean updated the motherboard BIOS from the BIOS, not just the Windows drivers for your motherboard?

One possibility for isolating the problem could be to install some variety of desktop Linux on one of the drives and trying to run some games with Proton. If this also fails I'd suspect there's some issue with a piece of hardware or its firmware. Also have you tried to update/reflash your MoBo BIOS?

Even if we can't solve your issue I commend you on doing troubleshooting, documenting it and giving us as much info as you can to work with! Though I'd like you to specify if Factory Reset on PC means you reinstalled Windows from a fresh USB/Disc or if you just did the built-in Windows factory reset?

Get a bigger SSD!

It's not the exhaust process. The card will blow air out of the back of the PC and whatever might flow out of the sides of the card will definitely make its way to be exhausted by one of the top fans! Dust might be a problem, but if it's not like absolutely filled with thick dust that wouldn't be causing such high temps. One thing I'd do though is making sure that the intake fans on the front are pushing in more air (spinning faster, or having more intake fans) than the exhaust fans are pushing out so that a positive air pressure is kept inside of the system. This will prevent dust from being sucked in from through nooks and crannies! However that's a small change and definitely not alone the cause of your high temps!

Might have some bullshit hotspot throttling if it's a Verizon phone. Damn that's sucky. Could be worse tough but still

Is it a carrier supplied phone?

I agree with the 1650 being a bit low powered for the configuration. Should be fine though if you're only going to be playing eSports titles.

There's like 1,5 fans just blowing fresh air underneath the GPU for it to use. Should be way enough, especially with such and open case!

He's got three fans pulling air in from the front. It most definitely isn't his overall airflow. I've got three intake fans, one outtake and a less open system. My Strix 1070ti barely reaches 70C at full load with <40% fan speed. EDIT: This is with F@H hitting my CPU 100% at the same time!

So if you go outside and test the phone on its own and as a hotspot (with the other device next to it) the speed is different? Well of course if you're going to be using a different ISP for the internet access then you can't use your phone to test it really. One option would be to get a prepaid SIM from said provider and test with it to see what the speeds will be like

The benefit of true G-SYNC was that it was the only way of getting VRR on Nvidia before they opened it up. Nowadays unless you're going for G-SYNC ultimate or need HDR or something it doesn't really matter if you get a G-Sync compatible or a G-SYNC proper monitor. I have both and I haven't observed any noticeable difference in the quality of the VRR

Your ping will definitely not be as good as with a wired connection, but as long as there's no bufferbloat on your side of the network latency shouldn't be much more than 20-30ms worse than a wired connection. If your phone isn't horribly old then you can go test the mobile network to your house simply by taking your phone, standing at the place in your home where you could mount an antenna and doing a speedtest. This should give you a rough estimate on what the speeds are going to be like. I would though recommend doing this in the evening when a lot of people will be possibly watching Netflix and doing other stuff on the cellular network, since that will be when the speeds are at their worst. Just make sure to get a good router! Either get one that is an antenna (like THIS one) or one that you can attach external antennae to.