Good afternoon and thank you for posting on the Final Fantasy XIV Technical Support Forums.

Have any changes happened to the device before the issue began? We would also like to recommend several other troubleshooting steps:

1) Make sure that your hardware is not overheating and remove any overclocks you may have on your graphics card or processor. Please check that any fans or vents are clear of blocks.
2) Disable any additional programs that could cause interference with the game itself including chat programs. Also, remove any custom configurations made using graphics driver-level programs.
3) Turn off Fullscreen Optimizations. Find the executable file for the game (normally found in the install folder), right-click it and select 'Properties'. Under the 'Compatibility' tab, check the box labeled 'Disable Fullscreen Optimizations', then click 'Apply'.
4) Remove any unnecessary USB or audio devices (controllers, headphones, flash drives etc.)
5) Update and reinstall the drivers for your graphics card
6) Install Steam, Windows and FINAL FANTASY XIV onto the same drive (Preferably the C:/ if possible).

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