When Windows shuts down my computer, I still have to turn off the monitor by pressing the power button. Is there a way to do this automatically?

Shalsim Shalsim

The short answer is no. Most VESA DPMS-compliant (Display Power Management Signaling) monitors have multiple power-saving modes, though, which are triggered by a signal from the computer. If there is no signal from the computer—as when it is off—the monitor goes into Power Off mode, which is the maximum power-saving mode. This turns off most of the monitor but leaves circuitry powered that wakes the monitor when the computer turns on again. Check your monitor's documentation.

You can expect the monitor to draw less than 5 watts of power in this nearly off mode. Twenty monitors in this mode would draw less power than a moderately bright light bulb, so the power consumption is negligible.