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Failing to boot to grub with dual boot Dell laptop
July 5, 2019
November 24, 2022
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You don’t have to switch to legacy mode to boot the Ubuntu Live USB. It’s a hybrid
.ISO that works in both CSM (legacy) and UEFI mode.
It’s not really an “EFI” partition but rather partitions are “MBR” (Master Boot Record) or “GPT” (GUID Partition Table). Generally speaking UEFI systems use GPT partitioned disks and CSM (legacy) systems use “MBR” partitioned disks.
The old days of “MBR” only allowed 4 primary partitions which could be divided into extended logical partitions. The new days of “GPT” allow many more partitions.
The important things to remember is most people suggest AHCI instead of Intel RAID is better to install Ubuntu. Also most people suggest Secure boot should be turned off.
Finally after installing you may still need to run