BIOS, diagnostics and other start-up notes

Crashed computer

Check the Recovering from a Major Hardware or Windows 10 Crash section

BIOS

Determining the BIOS version

The BIOS version is usually displayed quickly when a computer is booting, and when you are in the BIOS options screen

You can also get the BIOS version when your operating system is running!

From Windows

Use the msinfo32 command (i.e. type msinfo32 in the search field at the bottom left of the screen, and then launch the System Information app) and check the BIOS version line in the system summary screen. You will also get lots of other useful information about your computer (e.g. computer name)

From Linux

Use the dmidecode command: dmidecode -s bios-version

$ sudo dmidecode -s bios-version
[sudo] Password for your_login:
1.10.0

Entering the BIOS

Power off the machine, then power it on again and press repeatedly the appropriate key several times while the computer is starting, until you see the BIOS options screen. This should take place before you have to type the Windows bitlocker password, or the Linux (de)crypting password

Dell	`F2`
HP	`ESC` or `F10`

Enabling boot on a USB drive in the BIOS

Dell BIOS

Settings ⇒ General ⇒ Boot Sequence: USB Storage Device must be selected, and in the first place of the Boot Order

Updating the BIOS

Updating the BIOS is safe, but it may be a good idea to get help from somebody who has already done it. Your computer may restart several times, blink, etc, before the update is complete.

Be sure to be connected to a power supply during the update

If your Windows computer is protected by bitlocker at boot time, you have to suspend bitlocker (suspend, and not disable), before rebooting. more info

The BIOS update will take place during the boot time, then Windows will start and bitlocker will automatically start again

Dell:
- Healthy Windows computer:
  - Start the Dell Command Update program ,look for available updates (BIOS updates and others), and download them
    Start ⇒ Dell Command Update
  - check the Dell Support page, enter your Dell computer Serial Number (if it is not automatically detected), and check the BIOS related information
- Crashed Windows, or healthy (or crashed) Linux computer: use a USB stick to update the BIOS, following the steps in the How to recover from booting issues using the BIOS Recovery Tool video
HP:

If the BIOS update does not seem to work (no update takes place), check this HP BIOS update section
- HP Consumer Desktop PCs - Updating the BIOS (Basic Input Output System)
- HP Consumer Notebook PCs - Updating the BIOS (Basic Input Output System)

Notes

There are lots of HP BIOS details in HP PC Commercial BIOS (UEFI) Setup - Administration Guide (pdf document)

Other start-up related notes

Choosing the boot media or the diagnostics

Dell	`F12` (enter the One-time Boot Menu)
HP	`ESC` and then `F2`

Booting in safe mode

Safe mode ⇔ Mode sans échec

Windows 10

Read the Windows Recovery Environment (Windows RE) and the Safe Mode notes

Windows 7

Power off the machine, then power it and press the appropriate key at the same time

Dell	`F8`
HP