HP EliteBook 820 G1 - Page 178

Non Volatile
Memory
Type
Amount
(Size)
Does this
memory
store
customer
data?
Does this
memory
retain data
when power
is removed?
What is the
purpose of
this
memory?
How is data
input into
this
memory?
How is this
memory
write
protected?
Keyboard ROM 64 KBytes (not
customer
accessible)
No Yes Stores firmware
code
(keyboard,
mouse, &
battery
management).
Programmed at
the factory.
Code is
updated when
the system BIOS
is updated.
A utility is
required for
writing data to
this memory
and is available
on the HP
website.
Writing data to
this ROM in an
inappropriate
manner can
render the PC
nonfunctional.
DIMM Serial
Presence Detect
(SPD)
configuration
data
256 Bytes per
memory
module, 128
Bytes
programmable
(not customer
accessible)
No Yes Stores memory
module
information.
Programmed by
the memory
vendor.
Data cannot be
written to this
memory when
the module is
installed in a
PC. The specific
write protection
method varies
by memory
vendor.
System BIOS 4 to 5 MBytes Yes Yes Store system
BIOS code and
PC
configuration
data.
System BIOS
code is
programmed at
the factory.
Code is
updated when
the system BIOS
is updated.
Configuration
data and
settings are
input using the
F10 setup utility
or a custom
utility.
A utility is
required for
writing data to
this memory
and is available
on the HP
website.
Writing data to
this ROM in an
inappropriate
manner can
render the PC
nonfunctional.
168 Chapter 10 Statement of Volatility ENWW