Unfortunately yes.

You may want to look at this thread:

https://forums.totalwar.org/vb/showthread.php?t=69367

A lot of the issues there apply to STW as well (both games are basically the same game engine) so you may want to try out some of the fixes that may apply. Towards the end of the thread I posted some settings that worked for me with a 7xxx series card, though no one else has had any luck with these using an 8xxx series.