fedora 20 boot hang

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I installed from DVD (USB DVD drive) and there was also a removable USB hard drive that I mistakenly left attached during the install, in addtion to a number of other internal hard drives. fdisk listing (abbreviated):

Disk /dev/sda: 1.8 TiB, 2000398934016 bytes, 3907029168 sectors
Disk /dev/sdb: 1.8 TiB, 2000398934016 bytes, 3907029168 sectors
# the following (/dev/sdc) is the USB hard drive
Disk /dev/sdc: 931.5 GiB, 1000204885504 bytes, 1953525167 sectors
# /dev/sdd ->  (RAID controller volume 1): OS installation
Disk /dev/sdd: 931.3 GiB, 999989182464 bytes, 1953103872 sectors
# /dev/sde -> (RAID controller volume 2)
Disk /dev/sde: 2.7 TiB, 2999967547392 bytes, 5859311616 sectors

If I remove the USB drive (/dev/sdc), boot hangs