I thought I would share this as I had this problem for 3 weeks and ZoS support has not been helpful.
Do NOT do the below :
-delete add-ons
- open ports
- re-install / re-download
(those are ZoS Support responses and do not help)
The solution :
https://www.youtube.com/watch?v=-9GBjtafTuE
From reddit :
"nz_sekta
·
You may have a messed up shader cache file or no cache at all. Delete shadercache.cooked in your ESO documents folder and edit UserSettings.txt and make sure you have this line: SET CachedRLREnabled "1". Log in, should take a while as it builds the cache. After that it should be fast every time."
@ZOS_BillE
Please sticky this.