Partitioning Your Hard Disk

There are several reasons why you might want to divide your hard disk into partitions. For example, you might want to keep your operating system and your data on two different partitions. That way you can re-install the operating system (or a different operating system) without losing your data. Or, you might want to be able to dual-boot or multi-boot with different operating systems on the same computer.

There are several ways to partition a hard disk. If you already have data on the disk, then you need Partition Magic or System Commander. Both of these utilities come with a nondestructive partitioner.

If you can lose the data on the hard disk, You can use the fdisk DOS utility. If you are adding a second drive, you can run fdisk from the MS-DOS prompt in Windows. If you are repartitioning your old drive, you can place a copy of fdisk.exe and on a boot disk.

Note: Older hard drives used an overlay driver program to support partitions over 512MB. You can’t use fdisk with a drive that uses an overlay driver.

New hard drives usually come with a partitioning utility on a floppy disk. And, most operating systems can partition the hard disk as the first step of setup.

There are two kinds of partitions, primary and extended. An operating system must be on a primary partition. A hard drive can have up to four primary partitions. If you use fdisk to create partitions, be sure to set the partition you want to boot from as active. If you want more than four partitions, you can create three primary partitions, and one extended partition. The extended partition can be divided into logical drives until you run out of letters of the alphabet.

If want even more partitions, or more storage space, you can install a second hard drive. Each ATA (EIDE) channel on your motherboard can accommodate two hard drives. One drive will be the master, the other will be the slave. A jumper on the hard drive is used to set which is the master and which is the slave. Some computers use the drives position on the interface cable to define the master and slave.

Note: You may need to set your computers BIOS to recognize a second drive. This is done by pressing the appropriate key (usually Del, Esc, F1 or F2) during boot-up.

Windows always labels the active primary partition as C:\. Other primary partitions are labeled D:\, E:\...and so on, then logical drives are labeled. If you have more than one hard drive, then the first primary partition on the second drive is always labeled D:\, the first primary partition on the third drive is labeled E:\... and so on. Then the next letter is assigned to the second partition on the first drive.

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