With the latest releases, we are aware that many users are experiencing a variety of similar crashes with the error message: Unreal Engine is exiting due to D3D device being lost. (Error: 0x887A0006 - ‘HUNG’). For these crashes, something is causing your graphics card to hang, and the engine responds by crashing. Here is the link to the #1 crash in 4.14 - Unreal Engine Issues and Bug Tracker (UE-37999)
Unfortunately we have not been able to reproduce this crash internally at Epic, and we have not been able to narrow down any specific hardware or drivers that contribute to the issue.
If you are able to determine a definite reproduction case (especially if it occurs across multiple computers), please share the details with us!
Additionally, we would appreciate anyone who is experiencing a crash like this to run the UE4Editor.exe with the command line: -d3ddebug
This will add additional DX information to your project logs. After you crash, please gather the log file and attach it to a post in the Bug Report section on the UE4 Answerhub (additional information about how to log a bug report in my signature)
Thank you for your help.