Why do I turn off the power of a computer
It is also possible that the battery has been unable to store energy, can be filled with electricity on the other computer to see if there is a problem, you need to replace the battery.
Such as: use the battery, how close the monitor.
If not, right click on the desktop - properties - screen saver - power to see if the settings are correct.
Right click on my computer - Management - Device Manager - whether the battery is disabled, if it is disabled on the open, you can.