- Feb 6, 2015
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System: Dell Inspiron 546
Motherboard: DELL F896N 0896N
Issue: Some CMOS settings are not retained after saving and reboot.
Some CMOS / BIOS are retained. Time and Date are retained. Tested by setting arbitrary time and date, which persisted after reboot. Also retained after power unplugged.
Most are not retained. If I disable USB, set a boot device priority, or disable Onboard Audio, for example, the settings are reverted to defaults after reboot. I am using F10 to save. I have also used “Save & Exit Setup” in the AMI menu. Because of this I cannot leave a USB flash drive connected because the system will refuse to boot complaining about no OS installed as it is trying to boot from the USB flash drive instead of the hard drive.
My attempts to resolve thus far include: Update the BIOS to the latest available from Dell. Reset CMOS via mobo jumper. Check jumper position. Installed new CMOS battery that tests 3v good on voltmeter.
* Replacement CMOS battery does not resolve, voltage verified
* BIOS update does not resolve, however, update firmware is retained
* CMOS reset jumper position 1, 2 and open all tested
Consider the fact that a firmware flash to new firmware remains persistent as well as the time and date setting after a reboot…
The updated firmware would be written to the EEPROM memory of the ROM BIOS, which is a different chip than the NVRAM CMOS chip. This seems to explain why the new BIOS version is retained.
I’m speculating that since the system Date and Time is stored in the 14 bytes of RAM on the CMOS chip while the more advanced settings, as in most other settings including boot order, are stored in the southbridge or Super I/O chips. Following that reasoning, based on my understanding of things, is it possible that NVRAM on those “other chips” are faulty, and not the CMOS NVRAM?
Even setting a CMOS password is not retained after reboot. Only the Date and Time are retained. All other settings are lost after reboot. The system works, and loads Windows, but annoyances are created like it constantly tries to PXE boot and a keypress is required to tell it to skip and boot hard drive. If a thumb drive is left in the system or a disc the system will not boot with “no OS found.” Some of the CMOS defaults are problematic.
Please advise.
Motherboard: DELL F896N 0896N
Issue: Some CMOS settings are not retained after saving and reboot.
Some CMOS / BIOS are retained. Time and Date are retained. Tested by setting arbitrary time and date, which persisted after reboot. Also retained after power unplugged.
Most are not retained. If I disable USB, set a boot device priority, or disable Onboard Audio, for example, the settings are reverted to defaults after reboot. I am using F10 to save. I have also used “Save & Exit Setup” in the AMI menu. Because of this I cannot leave a USB flash drive connected because the system will refuse to boot complaining about no OS installed as it is trying to boot from the USB flash drive instead of the hard drive.
My attempts to resolve thus far include: Update the BIOS to the latest available from Dell. Reset CMOS via mobo jumper. Check jumper position. Installed new CMOS battery that tests 3v good on voltmeter.
* Replacement CMOS battery does not resolve, voltage verified
* BIOS update does not resolve, however, update firmware is retained
* CMOS reset jumper position 1, 2 and open all tested
Consider the fact that a firmware flash to new firmware remains persistent as well as the time and date setting after a reboot…
The updated firmware would be written to the EEPROM memory of the ROM BIOS, which is a different chip than the NVRAM CMOS chip. This seems to explain why the new BIOS version is retained.
I’m speculating that since the system Date and Time is stored in the 14 bytes of RAM on the CMOS chip while the more advanced settings, as in most other settings including boot order, are stored in the southbridge or Super I/O chips. Following that reasoning, based on my understanding of things, is it possible that NVRAM on those “other chips” are faulty, and not the CMOS NVRAM?
Even setting a CMOS password is not retained after reboot. Only the Date and Time are retained. All other settings are lost after reboot. The system works, and loads Windows, but annoyances are created like it constantly tries to PXE boot and a keypress is required to tell it to skip and boot hard drive. If a thumb drive is left in the system or a disc the system will not boot with “no OS found.” Some of the CMOS defaults are problematic.
Please advise.
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