Asus RS100-E4/PI2 - Manual (Page 121)

ASUS RS100-E4/PI2 6-23
3. When prompted, press the <SpaceBar> to select Yes from the
Initialize? dialog box, then press <Enter>. You may also press <F10>
to initialize the drive without confirmation.
Initializing a logical drive(s) erases all data on the drive.
4. A progress bar appears on screen. If desired, press <Esc> to abort
initialization.