XPS 15 7590 with Thunderbolt dock and an older Asus 22" external monitor connected to the dock with a VGA to Thunderbolt 3 adapter. It's hit and miss as to whether external monitor wakes with the computer after sleeping. For now I'm having to disconnected the Thunderbolt cable from the dock at the computer, wait for it to reset to a single display, and then plug it back in and wait for it to set itself back up for an extended display. It's a little annoying.