Defragmentation
I will end this test session with our homemade test of defragmentation speed. It is designed very simply: we took a HDD with one 32GB partition and installed Windows XP SP2 on it. Then we loaded the disk with music and photos, installed applications and games. We deleted some folders and installed new applications and created new files again. To cut it short, we tried to cause such a chaos that an active user of broadband Internet who doesn’t know anything about defragmenters can create on his Hard Disk.
We saved a per-sector copy of the disk and now copy it to the HDD we want to test. The tested HDD is connected to the mainboard’s SATA controller whose operation mode (AHCI/Standard SATA) is controlled from the mainboard’s BIOS. Next we run a FC-Test script that evokes the console version of the Perfect Disk 8.0 defragmenter and marks the time of the beginning and end of the defragmentation process.
Thus, each HDD is tested twice: with the controller’s AHCI support enabled and disabled.
Here are the results:

You can see the Hitachi drives are the only ones to benefit from the switching of the SATA controller into the AHCI mode. Considering the poor results of the Seagate drives, which have shown a good implementation of NCQ earlier, there is only one logical conclusion: NCQ has nothing to do with defragmentation. When the operation mode of the mainboard’s SATA controller changes, the disk driver changes, too. So, it is the different driver that provokes the difference in the drive’s performance in our defragmentation test.
This test is won by the Samsung, the Hitachi team taking second and third places. The Western Digital drive is good, too. Despite its lower spindle rotation speed, it competes with the Hitachi drives. This proves again how important the firmware algorithms are.