: Use your GPU's control panel (NVIDIA Control Panel or AMD Radeon Settings) or a tool like Special K to cap the game's frame rate at exactly 60 FPS (or even 30 FPS) before entering the Observatory.
Released in 2010 as a bridge between the classic Sands of Time trilogy and the ill-fated 2008 reboot, Prince of Persia: The Forgotten Sands is largely remembered for its fluid acrobatics, satisfying elemental powers, and massive scale. However, like many PC ports of that era, it shipped with a handful of game-breaking bugs. Among these, one stands out as a notorious run-ender: . prince of persia the forgotten sands the observatory bug fix
Here is a for The Observatory.