I have a problem with my Dell Latitude E5550 laptop, in particular with its display.
This laptop has been sat under my desk (unused) for quite a while and I wanted to reinstall Windows and use it for some ad-hoc testing.
However, I am struggling with the display, which is playing up.
1) When the laptop is left switched off, after switching it back on the internal LCD does not work. No images are displayed at all - no DELL logo on POST, no messages, no Windows desktop. But I can hear that Windows starts up correctly, so no issues with the rest of the system - must be related to graphic card or LCD.
2) If I connect an external HDMI monitor at this stage, it is not detected.
3) If I switch off the laptop, connect the external monitor and then switch it back on (with external monitor connected), it will work. I.e. Dell logo on post will be displayed and I will be able to see Windows desktop once it boots. But laptop's built-in screen will still be off and will not be detected in Windows at all (i.e. Windows only sees a single screen - the external monitor).
4) This is when it gets interesting: if at this stage I update BIOS using Dell BIOS update utility (to the same, latest version), the laptop's screen start working again. When the computer restarts and BIOS flash process starts, the internal laptop's LCD kicks back to life and all the BIOS reflash related messages are displayed correctly.
5) Following the BIOS reflash, the internal monitor keeps working correctly. If I disconnect the external monitor at this stage - it remains working. If I restart the laptop with the external monitor disconnected, the internal LCD keeps working. I can see Windows desktop and the built-in display is detected correctly in Device Manager.
6) If I then switch the laptop off again for a few hours, the process repeats itself, i.e. the internal LCD stops working and I have to follow the same procedure again (steps 1 to 5) to bring it back to life.
Not sure why, but it seems like reflashing BIOS fixes it for a while.
Same behaviour on battery and with the charger connected.
Tried downgrading BIOS (tried two older versions), but it did not make any difference.
I replaced the CMOS battery already and reset BIOS to defaults.
Tried LCD diagnostic (hold "D" key when switching on) which works fine, i.e. all colours are displayed correctly during the test.
Looks like this is not a problem with the LCD itself, but possibly motherboard or the BIOS?
Has anyone seen something similar on a Dell laptop?
This laptop has been sat under my desk (unused) for quite a while and I wanted to reinstall Windows and use it for some ad-hoc testing.
However, I am struggling with the display, which is playing up.
1) When the laptop is left switched off, after switching it back on the internal LCD does not work. No images are displayed at all - no DELL logo on POST, no messages, no Windows desktop. But I can hear that Windows starts up correctly, so no issues with the rest of the system - must be related to graphic card or LCD.
2) If I connect an external HDMI monitor at this stage, it is not detected.
3) If I switch off the laptop, connect the external monitor and then switch it back on (with external monitor connected), it will work. I.e. Dell logo on post will be displayed and I will be able to see Windows desktop once it boots. But laptop's built-in screen will still be off and will not be detected in Windows at all (i.e. Windows only sees a single screen - the external monitor).
4) This is when it gets interesting: if at this stage I update BIOS using Dell BIOS update utility (to the same, latest version), the laptop's screen start working again. When the computer restarts and BIOS flash process starts, the internal laptop's LCD kicks back to life and all the BIOS reflash related messages are displayed correctly.
5) Following the BIOS reflash, the internal monitor keeps working correctly. If I disconnect the external monitor at this stage - it remains working. If I restart the laptop with the external monitor disconnected, the internal LCD keeps working. I can see Windows desktop and the built-in display is detected correctly in Device Manager.
6) If I then switch the laptop off again for a few hours, the process repeats itself, i.e. the internal LCD stops working and I have to follow the same procedure again (steps 1 to 5) to bring it back to life.
Not sure why, but it seems like reflashing BIOS fixes it for a while.
Same behaviour on battery and with the charger connected.
Tried downgrading BIOS (tried two older versions), but it did not make any difference.
I replaced the CMOS battery already and reset BIOS to defaults.
Tried LCD diagnostic (hold "D" key when switching on) which works fine, i.e. all colours are displayed correctly during the test.
Looks like this is not a problem with the LCD itself, but possibly motherboard or the BIOS?
Has anyone seen something similar on a Dell laptop?
