Until it stops breathing

The correct answer is until the PSU does that very satisfying fully discarded “click”. But the article brings up some interesting topics:

Raymond Chen published another story from the Windows development trenches…

If you hold a PC’s power button for 12 seconds, it will turn off at the hardware level without notifying the operating system. This is a safety feature so that you can turn of the computer even if the operating system’s “Shut down” command isn’t working.

After eight seconds of the power button being held down, the Windows kernel realizes that the user is trying to do a force-power-off of the system, and it quickly takes a kernel dump that can be uploaded to the Windows Error Reporting service the next time you turn the system on. (-Raymond Chen)

…

It seems that the length of time you need to hold down the power button to force a power-off is dependent on the motherboard in question, handled by a microcontroller or some other IC. Virtually every source I can find says this timing is set to about 4-5 seconds, which is quite a bit shorter than the number of seconds given by Chen. Perhaps motherboard manufacturers consider the 12 seconds to be too long, and just do their own thing, regardless what the ATX specification suggests?

What further complicates matters is that Chen details how the kernel dumps created after pressing the power button for 8 seconds do, in fact, get sent to Microsoft once the computer turns on again. In fact, he is one of the people who gets to see these dumps and respond to them, so obviously they are indeed rolling in. Does this mean there’s a huge number of computers out there that require you to hold down the power button for 12 seconds to force a shutdown that nobody’s ever seen?