Nonvolatile memory usage
Nonvolatile | Amount (Size) | Does this | Does this | What is the | How is data input into this | How is this memory |
Memory Type |
| memory | memory | purpose of this | memory? | |
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| store | retain data | memory? |
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| customer | when power |
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| data? | is removed? |
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HP Sure Start | 2 MBytes | No | Yes | Provides | Data cannot be written to this | This memory is protected |
flash (select |
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| protected | device via the host processor. | by the HP Sure Start |
models only) |
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| backup of | The content is managed | Embedded Controller. |
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| critical System | solely by the HP Sure Start |
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| BIOS code, EC | Embedded Controller. |
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| firmware, and |
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| critical PC |
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| configuration |
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| data for select |
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| platforms that |
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| support HP |
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| Sure Start. |
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| For more |
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| information, |
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| see Using HP |
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| Sure Start |
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| (select models |
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| only) |
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| on page 81. |
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Real Time Clock | 256 Bytes | No | Yes | Stores system | RTC battery | This memory is not write- |
(RTC) battery |
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| date and time | is programmed using the | protected. |
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| and noncritical | Computer Setup (BIOS), or |
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configuration |
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| data. | changing the Microsoft |
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memory |
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| Windows date & time. |
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Controller (NIC) | 64 KBytes (not | No | Yes | Stores NIC | NIC EEPROM is programmed | A utility is required to |
EEPROM | customer |
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| configuration | using a utility from the NIC | write data to this |
| accessible) |
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| and NIC | vendor that can be run from | memory and is available |
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| firmware. | DOS. | from the NIC vendor. |
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| Writing data to this ROM |
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| in an inappropriate |
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| manner will render the |
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| NIC |
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DIMM Serial | 256 Bytes per | No | Yes | Stores memory | DIMM SPD is programmed by | Data cannot be written to |
Presence Detect | memory |
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| module | the memory vendor. | this memory when the |
(SPD) | module, 128 |
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| information. |
| module is installed in a |
configuration data | Bytes |
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| PC. The specific write- |
| programmable |
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| protection method varies |
| (not customer |
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| by memory vendor. |
| accessible) |
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System BIOS | 4 MBytes to 5 | Yes | Yes | Stores system | System BIOS code is | NOTE: Writing data to |
| MBytes |
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| BIOS code and | programmed at the factory. | this ROM in an |
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| PC | Code is updated when the | inappropriate manner |
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| configuration | system BIOS is updated. | can render the PC non- |
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| data. | Configuration data and | functional. |
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| settings are input using the | A utility is required for |
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| Computer Setup (BIOS) or a | |
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| writing data to this | |
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| custom utility. | |
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| memory and is available | |
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| on the HP website; go to |
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| http://www.hp.com/ |
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| support, and select your |
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| country. Select Drivers & |
78 Chapter 10 Statement of memory volatility