Assuming you want to do it one time and not always have the USB as the first boot device try this. Start the system and at the Dell splash screen start tapping F12. You will see a list of boot options and the USB will be on the list (if you plugged it in before starting the system). Select the USB drive.
^ That's the most convenient way on all systems and the only practical way on UEFI systems. In the latter case, local storage boot options only get listed in the BIOS Setup interface if they've actually been registered into the UEFI firmware, and that registration points to a specific file of a specific partition on a specific device. That obviously isn't a desirable solution if you just need to boot off a USB device occasionally. By comparison, the F12 one-time boot menu's options are dynamically populated based on the devices that are connected at the time. And even on Legacy BIOS systems where you COULD adjust the boot order to put USB at the top, that's less convenient, because then you have to go back and undo it later.
JOcean
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January 29th, 2019 05:00
Assuming you want to do it one time and not always have the USB as the first boot device try this. Start the system and at the Dell splash screen start tapping F12. You will see a list of boot options and the USB will be on the list (if you plugged it in before starting the system). Select the USB drive.
jphughan
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14K Posts
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January 29th, 2019 09:00
^ That's the most convenient way on all systems and the only practical way on UEFI systems. In the latter case, local storage boot options only get listed in the BIOS Setup interface if they've actually been registered into the UEFI firmware, and that registration points to a specific file of a specific partition on a specific device. That obviously isn't a desirable solution if you just need to boot off a USB device occasionally. By comparison, the F12 one-time boot menu's options are dynamically populated based on the devices that are connected at the time. And even on Legacy BIOS systems where you COULD adjust the boot order to put USB at the top, that's less convenient, because then you have to go back and undo it later.