You can either boot the Windows NT CD-Rom or setup disks to start the
install. Depending on your drive's geometry Windows NT supports a system
partition (the first primary active partition and where the files required
to start the OS reside (boot sector)) limited to 7.8gB NTFS or 4gB Fat16,
while the boot partition (where the OS is installed) is not limited in size.
You wont be able to create a system partition greater than 4gB with Windows
NT Setup; if you need a system partition 4gB - 7.8 gB, you'll need to use
Partition Magic or use another NT machine to create the first primary active
partition. The system and boot partition can be the same partition.

If you created one large system/ boot partition > 7.8 gB and installed the
OS, it may work, but the problem is if you defragment the drive or service
pack the install and the files ntdetect.com, ntldr, boot.ini, and
ntbootdd.sys end up being relocated to a point beyond the 7.8 gB barrier,
then the bootstrap process wont be able to find them and the OS wont start.

Once the OS is installed you can use Disk Administrator to partition and
format the rest of your drive. You'll need atapi.sys from SP4 or later for
Windows NT to be able to recognize a drive larger than ~ 8 gB. See the first
article for the link and instructions.

Installing Windows NT on a Large IDE Hard Disk
http://support.microsoft.com/default.aspx?scid=KB;en-us;q197667

Windows NT 4.0 Supports Maximum of 7.8-GB System Partition
http://support.microsoft.com/default.aspx?scid=KB;en-us;q224526

Boot Partition Created During Setup Limited to 4 Gigabytes
http://support.microsoft.com/default.aspx?scid=KB;en-us;q119497

Windows NT Partitioning Rules During Setup
http://support.microsoft.com/default.aspx?scid=KB;en-us;q138364