All Dell system BIOS has a reset to DEFAULT option that resets all BIOS settings to the Dell Default Configuration for that system model.
Some Dell users have noticed that resetting the defaults in the BIOS MAY NOT reset the BIOS configuration to match the settings of the BIOS when the system shipped from Dell.
EXAMPLE: The Default setting for Fast Boot is "Thorough" but it is set to "Minimal" from the factory for faster boot times.
No cause information
On Dell Branded BIOS (OptiPlex, Latitude, Venue, so on) either the Load Defaults or the Restore Settings button restores the BIOS defaults.
On Phoenix Branded, or American Megatrends Branded BIOS systems pressing the F9 key in the BIOS loads defaults.
Some options in a system BIOS may be changed from the default setting during the manufacturing process for various reasons.
Some of these changes are predicated on optional hardware that is installed in the system. Other setting changes might be a result of Dell customer feedback of settings preferred by system users.
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