Dell Precision 7820 Owner's Manual page 89

7 A warning box is displayed asking you if you want to proceed. Click the Yes button to begin the flash.
8 At this point the BIOS flash will execute, the system will reboot and then the BIOS flash will start and a progress bar will show the
progress of the flash. Depending on the changes included in the update, the progress bar may go from zero to 100 multiple times and
the flash process could take as long as 10 minutes. Generally this process takes two to three minutes.
System Setup 89