There's a new option "use fdisk" in the installer (GREAT! I need that!) - unfortunately, it's not explained in the help text. People from the DOS/SuckOS 98 world will assume fdisk == the only partitioning tool in the world, so use fdisk == run the partitioner.
Added to future feature requests.
GUI mode installer lacks help for screen offering fdisk as an option.
TUI mode currently has minimal help available about fdisk.
*** Bug 14988 has been marked as a duplicate of this bug. ***
The screens in the Red Hat Linux 7 installer have been changed so this should be