Definitions of gronk  

1. To clear the state of a wedged device and restart it. More severe than ‘to frob’ (sense 2).

2. [TMRC] To cut, sever, smash, or similarly disable.

3. The sound made by many 3.5-inch diskette drives. In particular, the microfloppies on a Commodore Amiga go “grink, gronk”.