Troubleshooting Heroes of the Storm and StarCraft II Performance
If you experience crashes, blue or black screens, performance issues, or your computer locks up while playing, follow the steps below to resolve these issues.
Overclocked Video Cards
Video cards modified to run at a higher clock speed, either by the user or the manufacturer, are not supported and may cause issues in StarCraft® II and Heroes of the Storm®. If you want to revert your video card settings, please contact your card's manufacturer for assistance before doing so. Nvidia® graphics card users can use these steps to determine if their card is overclocked.
Note: Factory overclocked cards may use terms like "Superclocked", "Turbo", or "Supercharged".
If the issue persists, uninstall your current copy of the game and reinstall the game from the Diablo III tab in the Battle.net App.