An Amiga 500 could smoothly scroll text vertically across a screen. An A500 ran with a CPU running at around 7MHz. A PC running windows with a CPU in excess of 2000Mhz doesn't seem to be capable of this feet why it that?
It has nothing to do with speed, timing rather.
The Amiga has a hardware vblank interrupt to handle scrolling and animation properly.
In Windows, updates to the screen have to be synchronized such that they never happen in the middle of the screen in order to have a smooth 60Hz display. This is in fact very difficult to do..