Windows 11 Pro, my PC will wake itself back up when sleeping & start itself back up when shut down

This is what fixed it for me, after trying around 10 things from online youtube videos and another 10+ things from discussions with Google's AI. Had the AI summarize it for a forum post after. I do not work in IT, do not speak the language and will not monitor this post. Just thought Id post it on a few forums since I couldnt find the solution online:

Fix: Windows 11 Instant Sleep Wakeup and Shutdown Restart Loop

If your PC immediately wakes up from sleep or restarts instead of shutting down, the Windows kernel is failing to send a clean power-down command to the motherboard. Forcing the kernel to explicitly cut power fixes both issues.

How to fix it via the Registry:

Press Win + R, type regedit, and press Enter to open the Registry Editor.

Navigate to the following path:

HKEY_LOCAL_MACHINE - SOFTWARE - Microsoft - Windows NT - CurrentVersion - Winlogon

In the right pane, look for the value named PowerDownAfterShutdown.

Double-click it, change the Value Data from 0 to 1, and click OK.

Restart your PC to apply the changes.

virus scans turn up nothing.

one thing i will note is i think this started after my tower fell over, and bent cpu pins - hence cpu replacement.   also when it does auto-wake itself, it almost never wakes successfully, so i just have to force shut down. which sometimes also does not work.

Another thing happening is it appears that my bios is resetting on every startup.

This usually happens because something is triggering your PC to wake up automatically, like scheduled tasks, network activity, or certain hardware settings. First thing I’d check is the power settings, go to advanced power options and disable “Allow wake timers”. Also open Device Manager and check your network adapter, then uncheck “Allow this device to wake the computer”. Sometimes Windows Update or maintenance tasks can also wake the system, so it’s worth checking the Task Scheduler for anything set to run automatically. If it’s even turning back on after shutdown, fast startup might be the cause, you can try disabling that in power options. It’s a bit of trial and error, but usually one of these settings fixes it.

This is abnormal. You need to run a virus scan first!