Samsung 940T 사용자 설명서

After pushing the "MENU" button more than 5 seconds, OSD function is 
locked (unlocked). 

You can also adjust the brightness and contrast of the 
monitor with the OSD adjustment locking feature.

Push the MagicBright button to circle through available preconfigured 
modes. 
- Six different modes (Custom/Text/Internet/Game/Sport/Movie)