I installed CentOS 7 on a Shuttle X27D box (dual-core Atom 330), and so far it seems to work fine, but it didn't set up a Grub2 entry for the existing Windows XP installation in the first partition (MBR). Running os-prober generates no output. fdisk shows that the NTFS partition is still present as /dev/sda1, and still has the bootable flag set. I added a menuentry for Windows to the end of /etc/grub.d/40_custom: menuentry "Windows" { set root=(hd0,1) chainloader +1 } and ran: grub2-mkconfig >/boot/grub2/grub.cfg and that lets me boot Windows, but I thought this was supposed to be taken care of automatically. Is there any known problem that prevents the installer or Grub2 from finding Windows XP? I don't normally set up dual-boot on production machines, but I use it a lot for testing. Thanks, Eric