3TB USB drive, only 800GB in size after formatting.

I have connected a 2nd USB drive, it's a 3TB drive. After partitioning it and formatting it to ext2, it only shows as being 800GB in size. Any ideas if I am doing something wrong or if this is a bug?

Here are the various outputs I get:

root@sheeva:~# fdisk -l
Note: sector size is 4096 (not 512)

Disk /dev/sda: 3000.5 GB, 3000592965632 bytes
255 heads, 63 sectors/track, 45600 cylinders
Units = cylinders of 16065 * 4096 = 65802240 bytes
Disk identifier: 0x7912ad63

Device Boot Start End Blocks Id System
/dev/sda1 1 45600 2930255748 83 Linux

Disk /dev/sdb: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x44fdfe06

Device Boot Start End Blocks Id System
/dev/sdb1 1 60801 488384001 c W95 FAT32 (LBA)

------------------------------------------------------------------------------------------------------------
root@sheeva:/dev/disk/by-id# mkfs.ext2 /dev/sda1
mke2fs 1.41.3 (12-Oct-2008)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
48930816 inodes, 195693025 blocks
9784651 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=0
5973 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872, 71663616, 78675968,
102400000

Writing inode tables: done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 20 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
root@sheeva:/dev/disk/by-id#

----------------------------------------------------------------------------------------------

root@sheeva:/mnt# df
Filesystem 1K-blocks Used Available Use% Mounted on
rootfs 519168 253868 265300 49% /
tmpfs 257816 0 257816 0% /lib/init/rw
varrun 257816 292 257524 1% /var/run
varlock 257816 0 257816 0% /var/lock
udev 257816 32 257784 1% /dev
tmpfs 257816 0 257816 0% /dev/shm
tmpfs 257816 21680 236136 9% /var/cache/apt
/dev/mmcblk0p1 15306620 1801832 12727244 13% /mnt/sd
/dev/sdb1 480719056 388076716 68223140 86% /mnt/share1
/dev/sda1 770488156 159932 731189620 1% /mnt/share2
root@sheeva:/mnt#

---------------------------------------------------------------------------------------------

root@sheeva:/mnt# fdisk /dev/sda1
Note: sector size is 4096 (not 512)
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel with disk identifier 0x3053b55f.
Changes will remain in memory only, until you decide to write them.
After that, of course, the previous content won't be recoverable.

The number of cylinders for this disk is set to 12181.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
(e.g., DOS FDISK, OS/2 FDISK)
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)

Command (m for help): p

Disk /dev/sda1: 801.5 GB, 801558630400 bytes
255 heads, 63 sectors/track, 12181 cylinders
Units = cylinders of 16065 * 4096 = 65802240 bytes
Disk identifier: 0x3053b55f

Device Boot Start End Blocks Id System