update:
The following setting recommended in the troubleshooting guide led to a stable hourlong sp session on low graphics:

Try right clicking the executable and selecting Properties. Then switch to the Compatibility tab and check off the 'Override high DPI scaling behavior' option (set it to Application). Run as administrator and disable fullscreen optimization and set a Win 7 or 8 compatibility mode. In Windows 7, check off the option to 'Disable display scaling on high DPI settings', then disable desktop composition and run as administrator.
https://larian.com/support/faqs/crashes-during-gameplay-pc_61

Looks like I'm able to play. Yet to be tested in multiplayer and with Discord running.