Most modern computers allow you to choose at startup which disk, partition or USB stick to boot, so you can install new versions of Windows or try one of the GNU / Linux distributions available at the moment. Unfortunately not all computers offer an easy method to boot the PC from the desired device: if the computer is old or has an unknown BIOS it may not be possible to boot it from USB or from an external disk, preventing us from trying new ways to restore or to test new operating systems.
In this guide we will show you how to boot the computer from USB on all modern systems and also how to use a special key capable of "bypassing" the BIOS and starting anyway, even on older PCs or on which it is impossible to access the screen of choice. boot disk.
READ ALSO -> How to change the boot order of the computer
1) Boot the computer from USB (standard method)
If the PC is sufficiently new and is not used in business, entering the boot options selection screen is very simple : we insert the USB stick that we intend to use at startup, from the PC off we repeatedly press F8 on the keyboard and start the machine by pressing the power button, continuing to press F8 repeatedly (with a little experience you will find the exact moment to press F8 to bring up the boot screen).
After the first boot screen, an overlay menu should appear where we can choose which disk or stick to use for booting.
Among the items present we find the one to start the DVD player or burner, the network boot and the items to start the removable devices.
On modern BIOSes you should directly see the name of the stick or external hard disk inserted in the USB port: select the right name to be able to boot the live system saved on it.
2) Boot the computer from USB (from BIOS)
If we cannot access the boot menu as seen in the previous chapter (the F8 key does not work or is broken), we can solve the problem by accessing the system BIOS directly, so as to change the behavior of the BIOS (which will start all first removable peripherals, then any disks present).
To make this change, with the PC turned off, we press the CANC key repeatedly and start the computer, without releasing the intermittent pressure on the button.
The key we recommended is not identical on all types of PCs and motherboards: in order to find the right sequence or the appropriate key to enter the BIOS or UEFI mode, we recommend that you read the guide on how to access the BIOS immediately on computers of all brands.
As soon as the BIOS or UEFI screen (the updated version) appears, go to the Start or Boot menu, then select the Boot Device Priority item .
Using the keys indicated in the right part of the window, we move the Removable devices and USB Devices items to the top of the list, so as to immediately allow the boot via USB stick or USB disk at each boot (in the absence of external drives, the boot will continue with the DVD player or internal disc).
Once the change has been applied, press F10 or go to the Exit -> Save and Exit menu to make the changes effective.
Now, when the computer is off, insert the stick or external disk to one of the free USB ports of the computer and proceed with the power on: without doing anything else, the BIOS will immediately try to boot from the removable peripherals, without the need to open the boot menu.
If the BIOS is locked with a password or is no longer accessible, we can still try to recover it by resetting the internal memory of the motherboard; this memory is maintained thanks to a button battery, which we must remove and reinstall.
To deepen this discussion, we invite you to read the following guide -> Reset the BIOS by clearing the CMOS memory and removing the buffer battery.
3) Boot the computer from USB (old PC or locked BIOS)
If our computer is unable to boot any removable media from USB, we can still obtain the desired result by downloading the Plop Boot Manager program which, in its standard use, can be copied directly to the stick or external disk to activate the option boot from USB without BIOS .
We download the compressed Plop file, decompress it and burn the plpbt.iso file on a blank CD or DVD.
If we don't know which programs to use for burning, we invite you to read the guide here -> How to Burn CDs and DVDs for free (Windows and Mac).
After creating the disc, we restart the computer with the disc inserted in the player or the burner: the system should automatically start the program included in the disc, without further steps.
If we do not see the Plop program appear, we repeatedly press the F8 key at startup with the disc inserted and select the player or burner as the boot drive.
Once in the start screen of the program we press on Plop Boot Manager to use an alternative boot menu, very effective on old computers or which do not support booting from removable devices.
Now that the start screen is displayed on our computer, we can insert the stick or external disk to one of the USB ports on the system: immediately the Plop program will notice the addition of external devices and will allow you to start them without problems, bypassing made any limitations of the BIOS or UEFI.
If we want to modify the boot items directly inside Windows, we invite you to read our guide to EasyBCD, the most powerful Windows tool to install two operating systems and manage the boot in a PC.
If instead we want to install Windows from a bootable USB stick, so as not to use the CDs or DVDs every time, we advise you to read the guide linked below, so as to find all the necessary steps.
READ ALSO -> Install Windows 7, Windows 8.1 and 10 from USB stick, without CD
