Comment 9 for bug 185878

same here. I was installing -server edition on new Lenovo TD100 ThinkServer machine. Originally I thought it was caused by RAID controller but obviously the problem is somewhere else. From my experience it's not limited to case with non-ext3 root partition. I had the same issue when I left the installer to partition my drives automatically (thus with ext3 root partition). In all the cases grub code was not installed into MBR *at all*. Being desperate I finally found out by dumping MBR...

It's broken completely, even if you go back at the end of installation wizard and explicitly run "install grub" option it's not installed. The only working solution is to run terminal, chroot to /target and run grub-install manually.