Question "Non-booting" issue

Oct 19, 2022

Let me run down my issue real briefly.
I bought this PC from a Customizer place in 2019 or 2020, whenever the RTX 2080 TI was one of the best cards.
Some time in the last half a year, it developed a fun problem where occasionally, I'd turn it back on from Sleep mode the previous morning, and it wouldn't boot.
Monitors say no output, the fan whirrs up high and stays there - there are no error beeps or any other indicators, and I assume Windows is aborted in the background.
The issue has since developed to largely prevent booting. I'd turn the PC on, and immediately, soon, or rarely even some times after it reaches Windows (11) - within the first minute - it would just decide "Nah" and do the same symptoms again. Technically though, it has booted, so it's not a boot issue per se, I'm just not sure what to call it.

Now, I sent this pc back and paid a fat chunk of change to possibly be scammed (by being told my CPU was dead, and I'm betting it's not. The scam lies in them talking me into an "upgrade", suitable motherboard included...) - since my PC was not fixed. I tried to get new parts in order of suspicion to replace possibly faulty parts; so compared to when the issues began, I have new


Bout the only 2 things in there that are the same are some extra fans, and the GPU - which is an in-warranty replacement for one that died spectacularly.
I don't suspect the GPU because generally, I see no problems during operation, outside or inside of (Very intensive) gaming sessions.
What I suspect is some kind of power problem; the computer, if left unpowered for a few hours or days, seems to behave for several days in a row, where the boot issue would have been so serious I would need upwards of 15 on \ off cycles to actually get it to boot once.
I'm in one of those cycles now. Since the last occurrence, it has behaved for 2 to 3 weeks and now 2 mornings in a row, from a clean shutdown, it has "failed to boot".

My own examinations :

Re-seated old RAM \ new RAM , checked connections, motherboard has the latest BIOS update as when I bought it, nothing funky looking in the BIOS itself, attempted to disconnect PSU plug from a multi-plug tower and straight into the wall in case the tower was malfunctioning, there are no POST BEEPS to identify any issues. Extensively cleaned the PC case before and after sending it off for repairs using compressed air, PC is seated above carpet on a wooden platform, away from ESD of any kind, ran regular and SMART diagnostics on my boot drive, it's in near perfect operating health without any flags of any kind.
I have had a boot where I got into Windows and saw my desktop, moved the mouse and opened apps at 9:25 AM, when it pulled it again : Screen went blank, "no display", fans whirr up high and stay there (Keyboard is backlit and responds with changing lights on attempted input). The important part here is, I made note of the time, went to Event Viewer and there was nothing in any tab for around 9:25 AM , where I am absolutely certain Windows had half a minute to do reports, logging and have its acceptable errors. I successfully booted to check this at 9:31 AM and found absolutely no entries, which is very sus to me, but I can't explain it.

I spent nearly the purchase value on the thing trying to fix it. I use it for large parts of each day for anything from work to leisure to research to socials and I'm at my wit's end. It simply wouldn't really want to boot near the end of July, causing me to have to be without it for a month - which is when I told the issue was "fixed". It's been sporadically displaying the same issue (less severely) since.

Current specs :

- Windows 11 21H2 (OS Build 22000.1098, HOME edition)
-Intel I9-12900K (Stock) (Also very new)
-RTX 2080 TI ( EVGA)
-Corsair 32 GB RAM (Very new, can be more exact if needed)
-850W PSU (I think EVGA? Replacing another 850W PSU that is likely also "fine", also very new)
-Boot drive is a very healthy Samsung Evo SSD, couple of years old - clean bill of health, no flags, SMART scan returns flawless

Additional information can be provided if necessary. I'm awful at just direct hardware stuff, so can't perform much jiggering due to massive anxiety.
Thanks for your time guys.