ErP and what it does.
Have you recently discovered that you cannot get your keyboard to power on your computer?
Did you used to have your computer wake up by mouse movement, or Lan signals? The answer is in the BIOS.
ErP Determines whether to let the system consume least power in S5 (shutdown) state. It is an energy saving mechanism in the BIOS. It will however, stop some functionality which you might want.
ErP mode disables the following four settings when it is enabled:
- PME Event Wake Up – PME is short for “power management event” and is responsible for devices—which do not have ErP enabled—turning on again spontaneously after being shut down by the user.
- Power On By Mouse – You will not be able to return the computer to a wake state by using the mouse.
- Power On By Keyboard – You will not be able to return the computer to a wake state by using the keyboard.
- Wake On LAN – Incoming signals from the LAN will not cause the machine to return to a wakeful, working state.
So that includes Power On By Keyboard, Power on by Mouse, or Power on By Lan. These options will be unavailable when ERP is enabled.
You can re-disable it on this screen. Platform Power > ERP Settings
What this means is that the computer will always be drawing up to 2W of power, in order to enable the options above. So if you want to wake up your computer with your mouse, keyboard or LAN, you need this power to be available and you need to disable the ERP to have those options.
Ultimately ERP is an energy saving function. ErP mode ensures that when a device is shut down, it remains shut down until the user intervenes (by directly pressing the power button, using a remote control to power on a device, etc.) The primary purpose behind the ErP standard is a green initiative to reduce the environmental impact of power losses when devices continue to consume electricity in a shutdown state.
However, a lot of customers do find the power on by keyboard and power on by mouse or LAN useful, so hopefully this article has shown how to get those things working that way again if you require it.