03-13-2019 08:14 PM
This is a Thinkpad E540 running Windows 10. I use both the laptop screen and an external HDMI monitor.
Coming back to the desk after I started a lengthy activity, I found that the laptop screen was black. Windows device manager only detects a single "generic PnP monitor". Lenovo's driver update includes an optional graphics driver update, but it fails. When rebooting, I see nothing on the screen, not even BIOS messages.
So, this looks like a hardware failure, but is there a possibility this can be caused by a software setting? Even if this is the hardware, I wonder if I can do something about it. Does the driver update provide details about the failure? Is there a diagnostic program that checks the hardware? Are there other measures I can take?
EDIT: I ran the diagnostics utility from the Lenovo Support web site. It ignores the laptop's display as if it didn't exist. I would have expected errors, at least. The external display is recognized and checked.
EDIT2: When booting, BIOS messages are displayed on the HDMI monitor. The BIOS dialogs allow me to specify the display. There are three options: Thinkpad LCD, HDMI and VGA. Although Thinkpad LCD is selected, output invariably goes to the HDMI port.