Lenovo ThinkPad X240, User Manual

Page: 144 / 181

1. Start Power Manager.
2. Click the Power plan tab, and then select Maximum Performance from the predefined power plans.
• Problem : When I turn on the computer, nothing is displayed on the screen and the computer does not
beep while starting up.
Note: If you are not sure whether you heard any beeps, turn off the computer by pressing and holding the
power button for four seconds or more. Then turn on the computer and listen again.
Solution : Make sure that:
– The ac power adapter is connected to the computer and the power cord is plugged into a working
electrical outlet.
– The computer is turned on. (Press the power button again for confirmation.)
– The brightness level of the screen is appropriately set.
If a power-on password is set, press any key to display the prompt for the power-on password and
then type the correct password and press
Enter .
If these items are correctly set, and the screen remains blank, have the computer serviced.
• Problem : When I turn on the computer, only a white cursor is displayed on a blank screen.
Solution : If you have modified a partition on your hard disk drive by using partition software, information
about that partition, or the master boot record might have been destroyed.
Do the following to try to solve the problem:
1. Turn off the computer, and then turn it on again.
2. If you still see only the cursor on the screen, do the following:
– If you have used partition software, examine the partition on the hard disk drive by using the
software, and recover the partition if required.
– Use the recovery solutions to restore the system to the factory default state.
If the problem persists, have the computer serviced.
• Problem : My screen goes blank while the computer is on.
Solution : Your screen saver or power management might have been enabled. Do one of the following:
– Touch the TrackPoint pointing device or the touch pad, or press a key to exit the screen saver.
– Press the power button to resume the computer from sleep or hibernation mode.
Beep errors
Table 6. Beep errors
Problem Solution
One short beep, pause, three short beeps, pause, three
more short beeps, and one short beep Have the computer serviced.
One long and two short beeps The video function has a problem. Have the computer
serviced.
Four cycles of four short beeps Shut down the computer immediately and have the
computer serviced.
Five short beeps The system board has a problem. Have the computer
serviced.
128
User Guide