Locking the game to 60 FPS is critical. Higher frame rates can "mess up" the physics in Kingdom Hearts 1 and 2, causing bosses to behave strangely or games to break entirely.
For a smoother experience, the community highly recommends the and KH-ReFined mods. Kingdom.Hearts.HD.1.5.and.2.5.ReMIX.Network.Fix...
Often installed via the OpenKH Mod Manager , this mod focuses on gameplay bugs and performance, making it a staple for modern PC play. Performance & Stability Tweaks Locking the game to 60 FPS is critical
Set the game to Windowed rather than Borderless or Fullscreen. You can then use tools like Borderless Gaming to fill the screen without triggering driver crashes. Kingdom.Hearts.HD.1.5.and.2.5.ReMIX.Network.Fix...