How long do you need to hold down the power button to turn off a PC?

A Windows developer explains that holding down a PC's power button for 12 seconds can turn off the computer at the hardware level, without notifying the operating system. This is a safety feature to allow shutdown in case the OS's 'Shut down' command isn't working. The Windows kernel takes a kernel dump after 8 seconds, which can be uploaded to Windows Error Reporting service the next time the system is turned on. The length of time to force a power-off is dependent on the motherboard, but most sources say it's 4-5 seconds, not 12 seconds. Chen questions this discrepancy and suggests that motherboard manufacturers may have their own settings.