I recently purchased a new box on which I wiped the drive and installed 
Linux using efi.  My efi partition is sda1, with Linux distributions on 
sda[2-3] and sda4 as swap.  However, if I don't have Windows, is there 
an advantage of using efi?  If I understand, I can enable legacy BIOS 
and lose the efi partition.  In that case I could have Linux 
distributions on sda[1-3].  I believe efi has effectively no partition 
limitations, so I could have efi on sda1, Linux distributions on 
sda[2-3] and sda5 as swap.  But I don't see the advantage of efi as four 
partitions is enough for me.

Also, while I'll probably keep my current setup, I realize the danger of 
not trying new things.  I'd like to attempt dual booting with Windows 
but am confused.  The default partitions were:

  *

    free space 1 MB

  *

    /dev/sda1 ntfs 1073 MB

  *

    /dev/sda2 efi 104 MB

  *

    /dev/sda3 ntfs 134 MB

  *

    /dev/sda4 ntfs 489243 MB

  *

    /dev/sda5 ntfs 9550 MB

  *

    free space 0 MB


I understand sda2 and assume sda4 is the main Windows partition. But 
what were sda3 and sda5?  Can I delete them?  Can I resize sda4 during 
my Linux installation?

I've not booted to Windows since 2002 and probably still won't after 
this experiment.  But I'd be interested in Linux users' input.