How to Replace a Master Hard Drive

What is a master hard drive?

“Master” is a term that was commonly used with older style IDE (parallel ATA) drives. Two of these drives could be daisy chained together on the same 40 pin cable. For the computer to recognize both drives, each drive would have to be set differently. The main boot drive was called the master and would have a jumper set on it to tell the system that it was the master. If a second drive was on the cable, it would have a jumper that needed to be set to “slave.”

With the advent of Serial ATA (SATA), every hard drive is treated as a "master," so there is no jumper setting to worry about. When multiple SATA drives are in a system, they are assigned to different SATA ports, so the computer knows where they are. For the purpose of this discussion, consider the boot drive to be the hard drive from which the computer is loading the Windows operating system

Why do you need to replace a master hard drive?

Replacing a master hard drive is something you normally do for one of three reasons: (1) Hard drive failure, where the hard drive has stopped functioning; (2) Upgrades, where a larger drive is being installed; and (3) Converting from an IDE configuration to a faster SATA configuration.

Replacing a failed master hard drive

If a hard drive has failed because of mechanical or electronic problems, you will normally consider all the data on that drive as lost. Hopefully, you have a backup that isn’t very old, but if not you can always send it off to a place that specializes in data recovery. Still, you will need to replace the drive because without it you can’t use your computer.

The first step is removing the bad hard drive. You should always do this first so you are sure to purchase the correct type of replacement drive. If your bad drive is IDE, you need to buy a new IDE drive to replace it. If the dead drive is SATA, you’ll have to buy a SATA device to replace it. When you put the new drive in the computer, make sure you connect the cables the same way as the old one was connected. For IDE devices, make sure that the jumper for “master” is set correctly.

Finally, you will need to boot your computer on your Windows installation CD. When you power up the computer, go into the BIOS setup to make sure the option to boot on CD is enabled. Let the computer boot on the Windows CD and follow the prompts to install. After Windows installation is complete, reinstall any special drivers you need for your printer, scanner, etc. and reinstall all your software applications.

Upgrading a master hard drive

It’s time to replace master hard drives when Windows reports insufficient swap file space or if new applications won’t install because of inadequate free space. When this happens, you can upgrade to a larger hard drive while keeping your data intact. You will need a drive cloning program such as Symantec’s Ghost to complete this process. If you buy the program locally, it will have a boot CDROM included, but if you download your drive cloning program, you will need to create a boot CD yourself.

When you have your cloning boot CD ready in the computer’s CD ROM drive, shut your computer down, and install your new master hard drive in the position of the old master. In case of an IDE configuration, set the new drive to “master” and then set the existing drive as “slave.” If this is a SATA configuration, connect the new drive to the same port as your original drive and then connect your original drive to a second SATA port. When you power up the computer, check the BIOS to make sure the option to boot on CD is enabled.

Cloning the drive requires that you follow the program prompts once the computer boots. You must be very careful to choose the correct source and destination drive; else you could copy the empty drive to the old one and lose all your data. When the cloning process is complete, shut the computer down and remove your original drive. The computer should now boot on your new master drive.

Switching from IDE to SATA

SATA drives are much faster than IDE devices, so converting a system from IDE to SATA is a good way to improve system performance. Since many motherboards equipped for IDE do not have SATA ports at all, you may need to purchase a SATA controller card that plugs into one of the computer’s expansion slots. Some computers may have both IDE and SATA ports so you won’t need to buy anything extra.

After connecting the SATA drive, boot using a drive cloning CD and copy the drive image using the original IDE drive as the source and the new SATA drive as the destination. When the process is complete, remove the old drive from the system.

What do I do with my old drive?

Hard drives that have failed should either be sent off for recovery or destroyed. You don’t want anyone else getting their hands on your data. After upgrading from a working hard drive, you might want to keep it around as a backup to protect yourself from future data loss.