Open bug in launchpad.net
"Lenovo ThinkPad W540 docked with an ultradock. 3 external displays running on VGA, DVI and display port all connected to the dock. BIOS mode set to run external displays ONLY with nvidia chipset. prime-select nvidia run.
When running under 4.15.0-36-generic with nvidia 390.77-0ubuntu0.18.04.1 I boot and all three external displays run fine.
Upgrading to 4.15.0-38 and Xorg starts up, but none of the displays light up."
Cristian Aravena Romero (caravena)
It appears to be a kernel issue, per the downstream bug report.
Looks like it happened the same time as a kernel upgrade, but it's not a kernel issue, it looks like an nvidia driver issue.
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