Clearing NVRAM through Advanced mode of SCU (System Configuration Utility)

Note: The Maintenance switch (usually switch 6) does not clear corruption in NVRAM. The maintenance switch will cause the system to ignore NVRAM for the next startup. This is usually enough to boot your system if it is hanging before or during POST. NVRAM will remain corrupt if you choose to use the maintenance switch instead of Advanced mode of SCU.

Note: Through these steps, SCU (System Configuration Utility) can be run either from the System Partition by pressing F10 upon bootup, or you can run SCU from the set of 4 Compaq System Configuration floppies. SCU cannot be run from the SmartStart CD-ROM since you cannot get to the main menu from there. Also, the diagnostics cannot be run from the SmartStart CD-ROM, you can either run them from the System Partition or from the Compaq Server Diagnostics floppy.

Note: Make sure that the version of SCU (System Configuration Utility) that you use is later than the ROM’s installed in your system. If you get the latest SCU from, then you should be ok. SCU will not work properly if it is older than the firmware installed in the ROM’s (Items which have flashable firmware are: System Boards, Array Controllers, Hard Drives, and Tape Drives).

Preparation (See Problems / Recovery below to see why preparation is necessary):

Note: You may want to grab a blank dos formatted floppy to hold the inspect report, configuration backup, and .cfg files if you are running SCU and Diags from the F10 partition. If you are running SCU and Diags from floppy, then save the files on those disks.

Get an inspect report from diagnostics.

Run diagnostics from either the System Partition (by pressing F10) or the Compaq Server Diagnostics floppy. Choose "inspect computer" and wait (memory and SCSI take a long time). Choose "Save to File", make sure all items are checked, hit "OK", change output file name to "a:inspectb.out", insert a floppy if one is not present, then hit "OK", watch the floppy drive light to make sure it saved to the diskette.

Get a copy of NVRAM (Configuration Backup).

Run System configuration from either the System Partition or the SCU floppies. Choose "system configuration", choose "configuration backup", choose "backup to a System Configuration SCI file". Insert a floppy if one is not present, use "F7" to change the current directory to the floppy drive, choose "A:", enter a descriptive file name, type a description which identifies this server, press enter and watch the floppy drive light to make sure it saved to floppy.

Gather .CFG files (EISA configuration files) and Resources for EISA and ISA boards.

PCI boards do not require .CFG files, EISA boards always have .CFG files, ISA boards have a .CFG file created by you. If you have any non-Compaq EISA boards, then you will need to locate the .CFG files for those boards (Compaq EISA board .CFG files are already included with SCU so you don’t have to gather them). For the ISA boards, you can either locate the .CFG files you have already created, or you can create new ones for them. It is best to write down the settings your EISA and ISA boards are using as those do not appear in the inspect report. (Remember that PCI boards are listed in the Inspect report so you don’t have to write those down).


Clearing NVRAM through Advanced mode of SCU:

Run SCU from the system partition (by pressing F10) or from the 4 floppies.

Press any key to continue when you get to the intro screen.

On the Main Menu of SCU press Ctrl+A. You will receive a dialog box stating "Advanced mode is enabled."

Choose "System Configuration".

Choose "Configure Hardware".

(If prompted to auto configure, choose no.)

Choose "Review or modify hardware settings"

Choose "Step 3: View or edit details"

Page down twice, you should now see the "Advanced Features" section. (Note: This has nothing to do with the F7 key as seen at the bottom of the screen)

Choose "Erase Non-Volatile memory: Select to erase Non-Volatile memory"

Answer Yes to the next 2 red screens.

You will receive a last dialog box stating the following

Erase non-volatile memory

The system configuration has been

erased and non-volatile ram has been


Turn off the computer and run the

System configuration utility again.

Shut off the server for 30 seconds (to let the system settle down).

Power on, and follow the steps below to reconfigure without corrupting NVRAM. (If nvram becomes corrupt, you will have to repeat this section to clear it once again).

Reconfiguring after clearing NVRAM through advanced mode of SCU:

IMPORTANT NOTE: Now that you have cleared nvram, it is important that you do not corrupt it by using a backup .SCI file.

Run SCU from the System Partition or 4 floppies.

When prompted to "Auto Configure", you have 2 choices. If you have an Array Controller installed, you want to choose “NO", if you don’t have an Array Controller, then you can choose "YES".

If you chose "NO", then you need to go into "System Configuration", "Configure Hardware".

If prompted to "use a backup .SCI file," choose "NO." (The backup file could be corrupt and you will have accomplished nothing).

Choose the correct operating system.

Save your changes and exit.


Problems / Recovery:

If your operating system complains about Hardware Settings (memory addresses, irq’s or vectors, etc.) then you will need to adjust some of the settings in SCU. You can find the values you need in the Inspect report or in what you wrote down for the ISA / EISA boards. If the Inspect report doesn’t show the information you need, then you can use the backup copy of NVRAM to get the settings, then proceed to clear nvram once again, and then configure with the proper settings. If you need to do this, the instructions are below in the section "Getting information from your backup copy of NVRAM."

Getting information from the Inspect report:

The Inspect report is a text file which contains most of the resources your server uses. (Remember, you saved this to floppy as a:inspectb.out). Of most use will be the PCI information which is under the MISC section which is at the very end of the Inspect report. If you can’t find your values here, temporarily restore your copy of NVRAM, get your values, then clear out NVRAM one more time.

Getting information from your backup copy of NVRAM:

If you couldn’t get your resource information from the Inspect report then you can get your answer from the backup copy you made of NVRAM. Run SCU, choose "System Configuration", choose "Configuration Backup", choose "Restore from a System Configuration SCI file". Press "F7" to change the current directory, choose the "a:" drive, you will then see your file you saved, along with a description. Select your image and it will be placed in NVRAM. Select "Review or modify hardware settings", "Step 3: View or edit details". Now that the image is restored, get the settings you need for the resources (especially ISA and EISA boards), then proceed to clear out NVRAM one more time, be sure to skip the preparation steps this time as you already have that information on floppy. (Please don’t overwrite your inspect report nor the copy of NVRAM on the floppy until you get your server reconfigured properly). Don’t stop here, please run through clearing NVRAM and use the settings you found here to reconfigure; if you stop here, then you have not accomplished anything.


Additional SCU info on PCI, EISA, and ISA boards:

When using SCU to configure your server the following will occur regarding .CFG files:

PCI boards will be auto-detected.

EISA boards will require their .CFG file (Configuration File) that came with it.

ISA boards do not come with .CFG files; however, you do generate one through SCU when you install the board (You can either create a new .CFG file for it or you can find one you already created for it).

Why "lock" an ISA board:

After adding an ISA board to System Configuration, you then "lock" the board, which is accessible through F7 when you are in the "Configure Hardware" section of SCU. Locking the board is necessary to prevent other devices from using those resources you have already set aside for the ISA board.

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