xubuntu@xubuntu:~$ sudo fdisk -l

Disk /dev/sda: 80.0 GB, 80026361856 bytes
255 heads, 63 sectors/track, 9729 cylinders, total 156301488 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x11224d6c

   Device Boot      Start         End      Blocks   Id  System

Disk /dev/sdb: 320.1 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk /dev/sdb doesn't contain a valid partition table

Disk /dev/sdc: 2101 MB, 2101346304 bytes
65 heads, 62 sectors/track, 1018 cylinders, total 4104192 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00009ea5

   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1   *          62     4102539     2051239    b  W95 FAT32
xubuntu@xubuntu:~$ sudo time dd if=/dev/zero of=/dev/sdb
^C7598425+0 records in
7598425+0 records out
3890393600 bytes (3.9 GB) copied, 154.578 s, 25.2 MB/s
Command terminated by signal 2
0.01user 54.12system 2:34.57elapsed 35%CPU (0avgtext+0avgdata 932maxresident)k
7598432inputs+7598432outputs (0major+285minor)pagefaults 0swaps
xubuntu@xubuntu:~$ sudo time dd if=/dev/zero of=/dev/sdb bs=512
^C8153249+0 records in
8153249+0 records out
4174463488 bytes (4.2 GB) copied, 166.365 s, 25.1 MB/s
Command terminated by signal 2
0.04user 58.36system 2:46.36elapsed 35%CPU (0avgtext+0avgdata 928maxresident)k
8153256inputs+8153256outputs (0major+286minor)pagefaults 0swaps
xubuntu@xubuntu:~$ sudo time dd if=/dev/zero of=/dev/sdb bs=512
^C2976401+0 records in
2976401+0 records out
1523917312 bytes (1.5 GB) copied, 60.7338 s, 25.1 MB/s
Command terminated by signal 2
0.00user 21.33system 1:00.73elapsed 35%CPU (0avgtext+0avgdata 924maxresident)k
2976408inputs+2976408outputs (0major+284minor)pagefaults 0swaps
xubuntu@xubuntu:~$