Follow the guidelines below for the Intel Management Engine BIOS Extension (MEBx) Password Reset process for Skylake (OptiPlex 7040 etc.) desktop systems.
MEBx Password Reset for Skylake desktop systems such as the OptiPlex 7040
Skylake systems which have previously gone through set up and configuration using MEBx will not revert by selecting full un-provision in BIOS settings.
Older system versions of OptiPlex systems which used Legacy settings could undergo a reset by selection of settings in BIOS under the MEBx interface.
Skylake systems are unable to use BIOS options to reset the system settings in case of lock out. In order to restore MEBx to default settings (See Figure 1.), a CMOS reset using the RTCRST jumper pins on the motherboard must be completed.
Figure 1. - MEBx BIOS Menu
Use the RTCRST Reset Jumper .
MEBx Password Reset is completed using the Real Time Clock Reset (RTCRST) Jumper pins on the motherboard to Clear Previous Configurations
- Turn the system off and disconnect all cables and connected devices from the system
- Remove the system cover
- Locate the 2-pin password (PSWD) jumper on the system board
- Remove the 2-pin jumper plug
- Locate the 2-pin RTCRST jumper on the system board (usually located near the CMOS battery on desktop systems, see Figure 2. below for example)
Figure 2. - RTCRST Jumper on the motherboard
- Insert the removed password jumper plug to the RTCRST jumper pins
- Plug in the AC power and press on the power button (system does not power on) to clear the CMOS information then turn the system off completely
- Disconnect the AC power and wait for about 30 seconds
- Remove the jumper plug on the RTCRST jumper pins and insert it back to the password (PSWD) jumper pins on the system board
- Replace the system cover
- Connect back all the cables and devices then turn on the system.
: Should the jumpers be in a hard to reach location, or the system is a portable, the secondary option to remove the CMOS battery and drain all power from the system can be used.
- Remove battery from the system (In portables, the main system battery and the CMOS Backup battery)
- Drain all flea power from the system by pressing and holding the power button for 10+ seconds
- Replace the battery(s)
OptiPlex 3040, OptiPlex 5040, OptiPlex 7040, Dell Precision Tower 3420, Dell Precision Tower 3620