The PC doesn't completely shut down when I select 'Power > Shut Down'.
The PC doesn't completely shut down when I select 'Power > Shut Down'.
Over time, my PC hasn't completely shut down when I use the Shut Down option in Windows. Pressing Shut Down turns off the monitors and keyboard, but the CPU fan speeds up and the PC lights stay on. I have to keep pressing the power button on my case for it to fully power off. The main issue is that it happens unpredictably—sometimes, without any other steps needed. This random behavior is really frustrating, especially since it's been a persistent problem with my PC.
Enable disabling fastboot in the BIOS settings and also within the power options menu (control panel → Power Options → modify what the power button does → adjust available settings and uncheck "Turn on fast startup").
Verified that Windows Fast Startup and Fastboot in the BIOS were already turned off.
Check if the appropriate drivers are present for your motherboard chipset. Verify whether sleep modes are turned off or activated.
I didn't locate "Sleep States" in your BIOS (Z390 Phantom). However, I did find CPU C states, which you disabled. It appears your PC is shutting down completely now—this might not be the issue you were referring to. After some testing, it seems to function correctly again, though I haven't confirmed this yet. Just in case, I'll hold off on marking it as a solution until you verify further.