System Reboots spontaneously

[spitlist]

I have run hardware diagnostics for over 13 hours without any issues detected but when I try to use the PC, it continuously reboots.  I upgraded to Windows 11 and even tried going back to windows 10 but the problem persists.  Conveniently, the problem started right after the warranty expired.  At this point, I am considering scrapping the unit and buying anything but an HP.

[Prométhée]

Hello

[start]This is an automatic response
in order to avoid writing the same thing each time

Some elements may therefore not apply to you 
To be able to answer you effectively, we need some information

we need the exact model of your computer, and the product number
To find it follow this
for a desktop computer

HP Desktop PCs - How Do I Find My Model Number or Product Number? | HP® Customer Support
and for a laptop
HP Notebook PCs - How Do I Find My Product Name or Number? | HP® Customer Support

Give the full name with the product number P / N

this is not a model:
HP Desktop M01-F1xxx
the requested product number must look like this
Product Number: 9EE50AA # ABA
the model corresponding to this number will therefore be
HP Desktop - M01-F1033wb

Give the full version of windows

for windows 10 type winver in the search box
if you give the best information
your problem could have a solution more quickly (depending on the difficulty, of course)
Learn how to use the Community

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[spitlist]

Product is: 1J7L1AA#ABA

S/N: [personal info removed]

[Prométhée]

https://support.hp.com/us-en/product/hp-pavilion-desktop-pc-tp01-1000a/37921117/model/2100000357/doc...

Ok, so currently you have windows 10 again?
When the computer restarts, you don't do anything in particular, a while ago, or whatever
Did you install windows 10 only, nothing else or programs were installed afterwards?
At least check the temperatures

HWMONITOR | Softwares | CPUID

[spitlist]

I installed W10 along with all the other software I need on this PC and the system randomly reboots.  I originally thought it was a temperature issue but after running the HW Diags for a full day without any failures, I concluded it is a software issue.  But there is nothing that I can point to that tells me where the problem is.
I went ahead and reinstalled W10 again without any other software and still get the reboots.  It makes the computer totally useless.  I am thinking that it has a lot to do with the AMD processor because the HP Laptop I am also using had W10 and upgraded to W11 and has had no problems at all.

A friend who works for Microsoft suggested that it might have started after an update was installed.  That was when I decided to reinstall W10 again.  I got a reboot during the process of reinstalling the OS so that pretty much eliminates that possibility.  

I can't even go to HP for help because the failure seems to be in the way the software interfaces with the hardware and no diagnostic failures can be submitted to them.

I am about to buy another PC and it definitely won't have any other processor than an Intel Core i7.

[Prométhée]

see in the event viewer if not something special

there may be reboot, in case of updates, indeed ..
so, if windows has just been reinstalled, it is possible that this is a reason, so open windows update, to check!

so the temperatures?

[spitlist]

Here's the latest:
I installed another hard drive and attempted to install Windows again on that.  The problem persists with the new HDD.  That effectively eliminates the Hard Drive as the problem.
I reinstalled the old HDD and tried to install W10 and W11, but could never get either OS reinstalled.  I would get reboots during the copying of the OS files or after the files were loaded, and the installation proceeds, I would get the following message in a white box on the black screen:  

The computer restarted unexpectedly or encountered an unexpected error.  Windows installation cannot proceed.  To install Windows, click "OK" or restart the computer and then restart the installation."

So now, I am rerunning the HP Hardware Diagnostics in the "Run until an error is encountered" mode to see if I can force an error.  However, having done that before, I don't expect that any errors will be found.  This leads me to suspect that there is something in the system or BIOS that is not compatible with the current version of Windows 10 or 11.

I wish there was a way to talk to HP about the problem.

[spitlist]

Unfortunately, the event viewer is only available within Windows and since I cannot get the Windows Installation to finish, that option is not available.  I did try that earlier when Windows was loaded, but nothing was posting to that viewer.

Right now, I cannot get Windows to install properly and am stuck with that white background message I mentioned earlier.

[spitlist]

More on the subject:

I finally managed to get the OS (Win10) installed after multiple tries.  But in trying to load some software, It would reboot before the installation was complete requiring the process to be repeated multiple times.

I am sensing that it might be heat related, so I removed the CPU fan and smeared more Heat sink compound between the CPU and the base of the heat sink.  It seemed to help a bit but still rebooted continuously.  So I took a large floor fan and put it on top of the open case to see if that helped.  It did for a while but when I went back into the room where it is located, the monitor was at the light blue recovery screen.  I am still looking for answers.

[spitlist]

I finally managed to get to the event viewer and it would appear that the messages that are being generated when the reboots occur are something about the kernel power. Says that it rebooted without shutting down properly, stopped responding or lost power unexpectedly. Could it possibly be a power supply issue? If so, why would it not fail while running the HP hardware diagnostics?