Take the 2-minute tour ×
Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

I have a Windows 7 machine set up as a server. It has no monitor and is only accessed through remote desktop. I set up two scheduled tasks, one to put the computer to sleep at night and another to wake it up in the morning.

When it's woken up from sleep via a timer, it stays awake for only a couple minutes before going back to sleep. When woken up by pushing the power button, however, it stays awake all the way until the sleep timer. Why does my PC behave differently in these two scenarios?

I have set the PC not to prompt for a user's password on wake, since I worried that the login screen might follow different power rules. I tried SmartPower Configuration but had the same problems.

I can provide more details if questions are asked in the comments, but I'm not sure what's relevant.

share|improve this question

1 Answer 1

When it's woken up from sleep via a timer, it stays awake for only a couple minutes before going back to sleep.

This is because Windows has a second (hidden) timeout setting that it uses when a computer is woken "unattended" (i.e. by a timer). The timeout defaults to 2 minutes. You can reveal the hidden setting by altering the registry.

Find the following key in Registry Editor (regedit):

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Power\PowerSettings
\238C9FA8-0AAD-41ED-83F4-97BE242C8F20\7bc4a2f9-d8fc-4469-b07b-33eb785aaca0

There should be a DWORD named Attributes. Change its value to 0 (or anything other than 1).

When you next go to the advanced power settings you will see a new setting:

Advanced power settings dialog

To disable the timeout, change the value to 0 minutes.

P.S. The latest version of SmartPower will check this setting for you, and will offer to change it, if required.

P.P.S. Here's another guide to changing the setting. (The attached .reg files change Attributes to 2, but it has the same effect. 1 means "hidden", anything else means "visible").

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.