Dell DX6000 - Manual (Page 77)

Using the System Setup Program and UEFI Boot Manager 77
Entering the iDRAC Configuration Utility
1 Turn on or restart your system.
2 Press <Ctrl><E> when prompted during POST.
If your operating system begins to load before you press <Crtl><E>,
allow the system to finish booting, and then restart your system and
try again.