HP ENVY 17 Maintenance And Service Manual page 84

a. Turn on or restart the computer, and then quickly press esc.
b. Select Main, and then select Apply Factory Defaults and Exit.
c. Follow the on-screen instructions.
d. Select Main, select Save Changes and Exit, and then follow the on-screen instructions.
2. What is a UEFI BIOS, and how is it different from a legacy BIOS?
The Unified Extensible Firmware Interface (UEFI) BIOS is an industry-standard software interface
between the platform firmware and an operating system (OS). It is a replacement for the older BIOS
architecture, but supports much of the legacy BIOS functionality.
Like the legacy BIOS, the UEFI BIOS provides an interface to display the system information and
configuration settings and to change the configuration of your computer before an OS is loaded. BIOS
provides a secure run-time environment that supports a Graphic User Interface (GUI). In this
environment, you can use either a pointing device (touch screen, touchpad, pointing stick, or USB
mouse) or the keyboard to navigate and make menu and configuration selections. The UEFI BIOS also
contains basic system diagnostics.
The UEFI BIOS provides functionality beyond that of the legacy BIOS. In addition, the UEFI BIOS works to
initialize the computer's hardware before loading and executing the OS; the run-time environment
allows the loading and execution of software programs from storage devices to provide more
functionality, such as advanced hardware diagnostics (with the ability to display more detailed system
information) and advanced firmware management and recovery software.
HP has provided options in Computer Setup (BIOS) to allow you to run in legacy BIOS, if required by the
operating system. Examples of this requirement would be if you upgrade or downgrade the OS.
3. Where does the UEFI BIOS reside?
The UEFI BIOS resides on a flash memory chip. A utility must be used to write to the chip.
4. What kind of configuration data is stored on the DIMM Serial Presence Detect (SPD) memory
module? How would this data be written?
The DIMM SPD memory contains information about the memory module, such as size, serial number,
data width, speed/timing, voltage, and thermal information. This information is written by the module
manufacturer and stored on an EEPROM. This EEPROM cannot be written to when the memory module is
installed in a computer. Third-party tools do exist that can write to the EEPROM when the memory
module is not installed in a computer. Various third-party tools are available to read SPD memory.
5. What is meant by "Restore the nonvolatile memory found in Intel-based system boards"?
This message relates to clearing the Real Time Clock (RTC) CMOS memory that contains computer
configuration data.
6. How can the BIOS security be reset to factory defaults and data erased?
IMPORTANT:
These steps do not reset Custom Secure Boot Keys. See question and answer 7 for information about
resetting the keys.
a. Turn on or restart the computer, and then quickly press esc.
b. Select Main, and then select Reset Security to Factory Defaults.
76 Chapter 9 Statement of memory volatility
Resetting results in the loss of information.