Nonvolatile memory usage
Nonvolatile
Amount (Size)
Memory Type
HP Sure Start flash
2 MBytes
(select models
only)
Real Time Clock
256 Bytes
(RTC) battery
backed-up CMOS
configuration
memory
Controller (NIC)
64 KBytes (not
EEPROM
customer
accessible)
DIMM Serial
256 Bytes per
Presence Detect
memory
(SPD)
module, 128
configuration data
Bytes
programmable
(not customer
accessible)
System BIOS
4 MBytes to 5
MBytes
Does this
Does this
memory
memory
store
retain data
customer
when power
data?
is removed?
No
Yes
No
Yes
No
Yes
No
Yes
Yes
Yes
What is the
How is data input into this
purpose of this
memory?
memory?
Provides
Data cannot be written to this
protected
device via the host processor.
backup of
The content is managed
critical System
solely by the HP Sure Start
BIOS code, EC
Embedded Controller.
firmware, and
critical PC
configuration
data for select
platforms that
support HP
Sure Start.
For more
information,
see
Using HP
Sure Start
(select models
only)
on page
130.
Stores system
RTC battery backed-up CMOS
date and time
is programmed using the
and noncritical
Computer Setup (BIOS), or
data.
changing the Microsoft
Windows date & time.
Stores NIC
NIC EEPROM is programmed
configuration
using a utility from the NIC
and NIC
vendor that can be run from
firmware.
DOS.
Stores memory
DIMM SPD is programmed by
module
the memory vendor.
information.
Stores system
System BIOS code is
BIOS code and
programmed at the factory.
PC
Code is updated when the
configuration
system BIOS is updated.
data.
Configuration data and
settings are input using the
Computer Setup (BIOS) or a
custom utility.
How is this memory
write-protected?
This memory is protected
by the HP Sure Start
Embedded Controller.
This memory is not write-
protected.
A utility is required to
write data to this memory
and is available from the
NIC vendor. Writing data
to this ROM in an
inappropriate manner will
render the NIC non-
functional.
Data cannot be written to
this memory when the
module is installed in a
PC. The specific write-
protection method varies
by memory vendor.
NOTE:
Writing data to
this ROM in an
inappropriate manner can
render the PC non-
functional.
A utility is required for
writing data to this
memory and is available
on the HP website; go to
http://www.hp.com/
support, and select your
country. Select Drivers &
Nonvolatile memory usage 127