Re: Dell XPS13 ubuntu : delete EFI paritions, / not use UEFI ? what are the consequences
The EFI partition is required for UEFI booting. UEFI tends to boot faster than Legacy BIOS, and it also allows you to use things like Secure Boot (if your Linux distro supports it) and to use GPT disks, which in addition to being a more resilient setup than the older MBR layout allows more than 4 partitions on the disk if you ever want them. However, even if you wanted to switch to Legacy BIOS, which if anything would increase your boot time or at best leave it unchanged, you'd also have to reinstall everything from scratch because UEFI systems boot from GPT disks, whereas Legacy BIOS systems need MBR disks.