Nonvolatile memory
Nonvolatile
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?
HP Sure Start
flash (select
models only)
2-megabytes
No
Yes
Provides
protected
backup of critical
System BIOS
code, EC
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 118
.
Data cannot be
written to this
device via
the host
processor. The
content is
managed solely
by the HP Sure
Start Embedded
Controller.
This memory is
protected by
the HP Sure
Start Embedded
Controller.
Real Time Clock
(RTC) battery
backed-up CMOS
configuration
memory
256-bytes
No
Yes
Stores system
date and time
and noncritical
data.
RTC battery
backed-up CMOS
is programmed
using
the Computer
Setup (BIOS), or
changing
the Microsoft
Windows date
and time.
This memory is
not write-
protected.
Controller (NIC)
EEPROM
64-kilobytes
(not customer
accessible)
No
Yes
Stores NIC
configuration
and
NIC firmware.
NIC EEPROM is
programmed
using a utility
from the NIC
vendor that can
be run from DOS.
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.
DIMM Serial
Presence Detect
(SPD)
configuration
data
256-bytes per
memory
module, 128-
bytes
programmable
(not customer
accessible)
No
Yes
Stores memory
module
information.
DIMM SPD is
programmed by
the memory
vendor.
Data cannot be
written to this
memory when
the module is
installed in a
computer. The
specific write-
protection
method varies
by
memory vendor.
114 Appendix B Statement of memory volatility
