[code]fdisk -l
Disk /dev/sda: 320.1 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0009a645
Device Boot Start End Blocks Id System
/dev/sda1 * 1 24 192748+ 83 Linux
/dev/sda2 25 2456 19535040 83 Linux
/dev/sda3 2457 8535 48829567+ 83 Linux
/dev/sda4 8536 38913 244011285 5 Extended
/dev/sda5 8536 8796 2096451 82 Linux swap / Solaris
/dev/sda6 8797 11228 19535008+ 83 Linux
/dev/sda7 11229 14875 29294496 83 Linux
/dev/sda8 14876 38913 193084339 83 Linux
Disk /dev/sdc: 1500.3 GB, 1500301910016 bytes
255 heads, 63 sectors/track, 182401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00069279
Device Boot Start End Blocks Id System
/dev/sdc1 1 182402 1465137560 83 Linux
Disk /dev/sdb: 80.0 GB, 80026361856 bytes
255 heads, 63 sectors/track, 9729 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x000e0717
Device Boot Start End Blocks Id System
/dev/sdb1 * 1 5904 47423848+ 7 HPFS/NTFS
/dev/sdb2 5905 9729 30724312+ 7 HPFS/NTFS
Disk /dev/sdd: 320.1 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00026f1c
Device Boot Start End Blocks Id System
/dev/sdd1 1 38913 312568641 83 Linux[/code]
df -H
Sys. de fichiers Taille Util. Disp. Uti% Monté sur
/dev/sda2 21G 8,2G 12G 41% /
tmpfs 2,1G 0 2,1G 0% /lib/init/rw
udev 2,1G 328k 2,1G 1% /dev
tmpfs 2,1G 0 2,1G 0% /dev/shm
/dev/sda3 50G 45G 5,1G 90% /home
/dev/sdd1 321G 266G 55G 84% /Films
/dev/sda1 198M 55M 143M 28% /boot
/dev/sda8 198G 181G 17G 92% /provi
/dev/sdc1 1,5T 208M 1,5T 1% /stockage
effectivement df -H ne me donne pas du tout la même valeur que gparted 
Je vais rester quand même en ext4 
ça serait donc Gparted qui aurait tort et df raison
Merci à tous