So I updated my Nvidia drivers a few days back, and ever since Salem was completely screwed up.
My mouse was weird, had to restart client every 2 teleports because it would only register one out of 5 clicks / rightclicks, and there where screen refresh issues where I would see flashes of menu text at the top of my screen.
Game also lagged as if I was running 10 clients at once.
I tried reinstalling drivers, Java, and more. Nothing worked, game had become nearly unplayable.
In a moment of clarity, I suddenly got the idea that maybe, just maybe, javaw.exe was using my integrated intel graphics chip, instead of my Nvidia, favouring battery life over performance.
What I did is:
1) open Nvidia graphics settings (not the Geforce Experience, but the Nvidia config screen)
2) go to 'manage 3d settings
3) go to the program settings tab
4) click the add program button
5) select Javaw.exe. If you recently ran Salem, it will nicely show in the list of recently used programs
6) change the setting for the now added Javaw.exe, that says "automatic selection: integrated" to "powerful Nvidia processor"
7) click apply
8) enjoy your game running smoothly, and without weird issues
Before last driver update, it did use the Nvidia
So I guess what the latest driver update (v320.49) did, was change the parameters for automatic selection of which processor to use.
Hope this is helpful to those people who also experience problems after updating their driver.
Or in general for people who have two graphics chips on their laptops. Same problem might occur with different types of cards.