Hello guest :
You can update the BIOS from EFI shell as well . to go to EPI shell boot the machine.press F2/DEL key and enter in to BIOS setup and boot to EFI shell
If you have a latest BIOS in USB drive then type fs0: and apppropraite path.
Then update the BIOS and do AC cycle.Hope this solves your problem.
Other option is to boot the machine to Bootable USB drive(DOS) from there also you can update the BIOS.
Let me know if i can be of any assistance.
Every motherboard has almost the same way of BIOS upgradation even when done without an OS however it may vary a bit. Now as for the upgrade procedure, whatever motherboard you have, Intel site has it's BIOS upgrade along with an upgrade procedure mentioned in a text file attached along with it and this file not only includes BIOS upgrade procedure but also BIOS revision, updates, fixes, and even BIOS recovery. Since you have not specified the model of your motherboard, I will be quoting an example of S3000AH motherboard.
Simply look up SR1425BK1 on support.intel.com website.
Go to the page for the motherboard.
Click SUPPORT and under SOFTWARE AND DRIVERS section, select "BIOS/Firmware, driver and utilities download" BIOS/Firmware, drivers and utilities download
In the drop down menu, select "OS INDEPENDENT" and click GO
A page will open up and under the BIOS header, you will find something like this SR1425BK1 BIOS Update Package for DOS (3548KB)
Look up the latest version depending on release date and download it. You will note that there is a RELEASE NOTE.txt file with it which I was talking about earlier. In case you overlooked it, be sure to look into the zipped file that you downloaded.
Drill down the RELEASE NOTES or README.txt file and you will find the installation procedure mentioned which would look something like this:
============================================================================= IMPORTANT INSTALLATION NOTES ============================================================================= IMPORTANT NOTES: 1. Note the settings of the SETUP parameters. Enter SETUP by hitting the F2 key during boot up. Write down the settings for each of parameters. At the end of the BIOS update process you should set the parameters to default values by hitting the F9 key, and then re-enter these values you have written down. 2. Place the bootable floppy containing the BIOS into drive a: of the system that you want to upgrade and boot the system while the floppy diskette is in the drive. 3. There are 2 methods to flash BIOS. 3.1 Method 1: (1) Copy all of the following files into the same folder in Hard Drive or bootable USB Disk Key : BIO\1.bat BIO\AFUDOS.exe BIN\SBK1A001.rom (2) Go to this folder to run 1.bat and update finishes automatically. 3.2 Method 2: (1) Go to BIN folder and execute SBK1A001.EXE to make bootable floppy. (2) Use this bootable floppy to boot and update finishes automatically. 4. Once the system reboots after flashing to new BIOS or CMOS failed, it should finish POST within 2 minutes. Otherwise, it will roll to original (old) BIOS. 5. Enter Setup by pressing the F2 key during boot up. Once in Setup, press the F9 to set the parameters back to default values. Re-enter the values you wrote down at the beginning of this process. If you do not set the CMOS values back to defaults using the F9 key, the system may function erratically. NOTE: You may encounter a CMOS Checksum error or other problem after reboot. Try shutting down the system and booting up again. CMOS checksum errors require that you enter Setup, check your settings, save your settings, and exit Setup.
There you go, I hope you don't find it that complex however in case you encounter any problems, feel free to contact us any time.
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