Thanks for the update, and it's all good.

There was no issue with the game nor with what was on my computer. It, in fact, was definitely my GPU giving up. It overheated while I was playing TERA two days ago. Left it being halfway broken, thus I went to get a new one, and now everything is more than just fluent. Not one single FPS problem anywhere.

So I am sorry that I've wasted your time like that! But I appreciate the help you wished to provide and thank you for it a lot!

Have a nice day