Very low FPS, i used the compatibility mode with windows xp, vista, 95, 98 and it's not working, used patches from duranto. Nothing helped, game running like slide-show. Should i remove mode?

I don't use any unofficial patches or mods.

Initially when I first installed , the game ran at awfully low fps.
However, after few days (during which it ran the same) it suddenly started running fine. I am running win10 and I try to
keep my AMD driver up to date. Now I don't know what happened, or why it runs well now.

I know this is not really a helpful answer. I just shared my experience. :)
Maybe someone else may provide a better answer.

I turned off compatibility mode and game runs perfectly, but game crashed after hospital level.