DaCookieMonsta

Individual power cable to each port is best, the Y-splitter is not ideal because you're still restricted to one cable

Just out of curiosity, the 6900XT has two GPU power connectors- are they both connected to the PSU via dedicated individual cables for each? Some of the GPU cables have 2x 8pin connector bits which may be okay for lower-end GPUs but not for high power draw GPUs.

When booting LEDs will cycle through CPU>DRAM>VGA>BOOT With the BOOT LED being lit is when I'd expect Windows to start loading and then none of the LEDs are on. I suspect you're crashing and then your PC goes through the boot loop and you're stuck at the VGA part and then the BOOT LED not being triggered. I find it curious that the VGA LED is on for so long... Are you able to consistently replicate the crashes? I'm wondering if it is the GPU going funny, could be PSU but until testing I would just be guessing, if you have spare parts it's good for testing things out.

I live in a city where most the commutes are less than 8 miles the the cycle infrastructure is decent (but not NL-great) yet many otherwise fit and healthy people still use their cars because of convenience or because "it's just the way it is". EVs imo are an overcomplicated solution to a problem that can be resolved by old technology and frugal living, and the initial "investment" (no it is NOT an investment) is far bigger. For the price of a used EV, I can buy a small used ICE car with enough fuel to last 5 years.

You said there was POST while using the mobo GPU, you have visual via mobo GPU? I wouldn't normally expect that to be the case if you have a dedicated GPU plugged in, some mobos have an "auto switch" where if they detect a dedicated GPU the mobo GPU is turned off- let me know if I have misinterpreted your problem

Here is where it would really help if you had a spare PC to start swapping/testing... I'd do the "free" thing and check all connections but if the PC reacts the same manner even with the new PSU and nothing out of the ordinary took place with the PC by yourself then it's a little sus

Not enough details... Mobo (Asus something?), was this a new build, was the issue just occuring out of the blue or after an upgrade, etc.

There should be settings for this: Settings>Connections>SIM card manager Wifey has SIM1 configured for calls/messages and SIM2 for data

That's right at the cusp of "okay" and "inadequate" for your setup (which is insane btw), if it's an 80% efficiency PSU then you've got just under 700 watts to power the beast...

No details yet, was it just case and RGB fans? It's possible something got loose when you moved the mobo about so I'd check all the power cables, RAM, etc...

The termal paste suggestion as above- a lot of the times cheapo paste is used but you can for cheap still get a really good thermal paste, but also I'd invest in a laptop cooler, something USB power would be fine as long as it provides clearance at the bottom.

So your GPU runs games fine in another PC... I'd suspect PSU but before dipping into your pockets for a new PSU maybe swap the PSU from the good machine into the other but not other way round incase your suspect PSU is bad and it causes damage to your good mobo- I had a PSU that went bad that took the motherboard and GPU with it to the grave so no more cheap PSUs for me anymore. If you're still having issues, your mobo could be dodgy if you've ruled out the different PCIe slots. I'm not a PC tech by any means so please take what I say with a dose of salt =O

Going by the GT 750 GPU and DDR3, I'm assuming the PSU was original from 2014 as well? Almost 8 years old, at 230W I'd expect it to have lost some capacity quite a bit... If you can, time to fire the parts cannon if you have a spare PSU lying about.

Maybe fire the parts cannon? If you have a spare PSU lying about you can check with that, and spare GPU even... Or if you have a spare machine lying around swap the GPU/PSU and see if it gives same issue, you just need to see that you get some graphics output.

I wouldn't expect the CPU to overheat with a decent AIO unless heavy heavy loads... But the noise I've heard when either the water pump failed (but the noise persists) or if some cable is being hit by a fan upon startup (whateverybody else says!).