We’ve noticed this becoming a problem where people are upgrading their laptops, but the laptop manufacturers haven’t yet created the custom forks of Nvidia’s drivers that handle their hardware correctly.
I believe there is an option in the Nvidia Control Panel under the Desktop Menu>Display GPU Activity Icon in Notification Area. See if that option exists for you and let me know if it is switching to the Nvidia card when UE4 starts up.
If it is not starting up, then try going into the Nvidia Control Panel to the “Manage 3D Settings” option. Select “Program Settings”. If the 4.9 instance of UE4Editor.exe is not in the Program List, select add. Locate UE4Editor.exe (typically here: Program Files\Epic Games\4.9\Engine\Binaries\Win64) and then choose the preferred Graphics Processor in the list below.
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