Everything seems ok with your settings.
Only difference between EU and US version is that you should be getting max 25 fps instead of 30, there shouuldn't be any other speed difference.
Can you post a screenshot when it drops to 50% ?
Also, is sound ok when it drops ? Or does it stutter/skip ?
If sound is ok, then who cares
It might even be meant to drop, like Shonumi and I said it does drop to 20 fps instead of 30 in opening animation
Only difference between EU and US version is that you should be getting max 25 fps instead of 30, there shouuldn't be any other speed difference.
Can you post a screenshot when it drops to 50% ?
Also, is sound ok when it drops ? Or does it stutter/skip ?
If sound is ok, then who cares
It might even be meant to drop, like Shonumi and I said it does drop to 20 fps instead of 30 in opening animation