Lenovo ThinkPad X250 User Manual page 119

2. Turn on the external display.
3. Right-click on the desktop, and click Screen resolution.
Note: If your computer cannot detect the external display, click the Detect button.
4. Select the external display and set Resolution.
5. Click Advanced Settings.
6. Click the Monitor tab. Check the monitor information to make sure that the monitor type is correct.
If the monitor type is correct, click OK to close the window; otherwise proceed with the following steps.
1. If more than two monitor types are displayed, select Generic PnP Monitor or Generic Non-PnP
Monitor.
2. Click Properties. If you are prompted for an administrator password or confirmation, type the
password or provide confirmation.
3. Click the Driver tab.
4. Click Update Driver.
5. Click Browse my computer for driver software, and then click Let me pick from a list of device
drivers on my computer.
6. Clear the Show compatible hardware check box.
7. Select the correct manufacturer and model for the external monitor. If you cannot find your monitor
on the list, stop the installation of this driver and use the driver shipped with your monitor.
8. After updating the driver, click Close.
9. For the Windows 7 operating system, to change the color settings, right-click on the desktop, and
click Screen resolution. Click Advanced Settings, select the Monitor tab, then set Colors.
10. Click OK.
• Problem: Incorrect characters are displayed on the screen.
Solution: Did you install the operating system or program correctly? If they are installed and configured
correctly, have the computer serviced.
• Problem: The screen stays on even after you turn off your computer.
Solution: Press and hold the power button for four seconds or more to turn off your computer; then
turn it on again.
• Problem: Missing, discolored, or bright dots appear on the screen every time you turn on your computer.
Solution: This is an intrinsic characteristic of the TFT technology. Your computer display contains
multiple thin-film transistors (TFTs). A small number of missing, discolored, or bright dots on the screen
might exist all the time.
External display problems
• Problem: The external display is blank.
Solution: To bring up the image, press the display-mode switching key
monitor. If the problem persists, do the following:
1. Connect the external display to another computer to make sure that it works.
2. Reconnect the external display to your computer.
3. Refer to the manual shipped with the external display to check the resolutions and refresh rates that
are supported.
– If the external display supports the same resolution as the computer display or a higher resolution,
view output on the external display or on both the external display and the computer display.
and select the desired
.
Chapter 8 Troubleshooting computer problems
103