ThinkPad P50 User Manual page 115

• 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.
– If the external display supports a lower resolution than the computer display, view output on the
external display only. (If you view output on both the computer display and the external display, the
external display screen will be blank or distorted.)
• Problem: You cannot set a higher resolution than the present one on your external display.
Solution: Make sure that the monitor type and other information is correct by doing the following:
1. Connect the external display to the monitor connector, and then connect the monitor to an electrical
outlet.
2. Turn on the external display and the computer.
3. Right-click on the desktop, and do the following:
– For Windows 7: Click Screen resolution.
– For Windows 10: Click Display settings ➙ Advanced display settings.
Note: If your computer cannot detect the external display, click the Detect button.
4. Click the icon for the desired monitor (the Monitor-2 icon is for the external display).
5. Do the following:
– For Windows 7: Click Advanced settings.
– For Windows 10: Click Display adapter properties.
6. Click the Monitor tab. Check the monitor information to make sure that the monitor type is correct. If
it is, click OK to close the window; otherwise proceed with the following steps.
7. If more than two monitor types are displayed, select Generic PnP Monitor or Generic Non-PnP
Monitor.
Note: If the problem still is not solved, continue the following steps to update the monitor driver.
8. Click Properties. If you are prompted for an administrator password or confirmation, type the
password or provide confirmation.
9. Click the Driver tab, and then click Update driver.
10. Click Browse my computer for driver software, and then click Let me pick from a list of device
drivers on my computer.
11. Clear the Show compatible hardware check box.
and select the desired
.
Chapter 7 Troubleshooting computer problems
97