Have the same issue, Plex server crashes with exception code 0xc0000374 in the event logs every time I try and HW transcode running the latetst version of Plex server 1.18.1.1973, the computer continues to run and I have to re-launch Plex manually. Turned of HW transcoding and the issue goes away.
Windows 10, i5-4670, GTX 970 running the latest nVidia drivers.