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Hard Disk Basics

Installing a Hard Drive   Interface Specifications

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BIOS and Hard Disks
 Some older BIOS versions only support hard drives up to 528 MB. This problem can usually be solved by a BIOS update or with the addition of an ISA card meant to do exactly that—allow you to support larger hard drives.

Some newer BIOS only support drives up to 8.4 GB due to the lack of support for Logical Block Addressing (LBA), the newer type of drive geometry used in 8.4 GB and larger drives. Once again, a BIOS update usually does the trick.

Partitioning and file systems
 While there are many disk partitioning utilities out there, I will focus on Fdisk, which is the most common. The same general rules apply for the file systems regardless of what partitioning utility you use.

Using Fdisk to partition a drive is usually no fun task. Here are some tips to help you get through partitioning your hard drive:

Now is the time you need to decide what file system you would like to put on your computer. Here are some of the choices.

FAT16
 FAT16 is compatible with all versions of Windows, including 98, 95, and NT. Choose this system if you:

If you choose this file system, your partitions cannot be over 2,048 MB (2 GB). You can have as many 2,048-MB partitions as your disk allows. Each separate partition will appear as a different drive letter under Windows and DOS.

When creating your partitions, you should first create a Primary DOS Partition of 2,048 MB and then create an Extended DOS Partition to cover the rest of your drive space. Make sure that you set your Primary DOS Partition as bootable if that is necessary in your version of Fdisk.

FAT32
 FAT32 should be your file system of choice if you are only going to be using Windows 98 or Windows 95B with your system. FAT32 supports partitions of up to 2 terabytes, so with today's hard drives the only reason you would need to split up the drive is for organization. Sometimes the motherboard can have problems booting the computer if the boot partition is too large.

FAT32 can only be read by Windows 98, Windows 95B, Windows 2000, and some newer versions of UNIX. The benefit of FAT32, other than support for larger partitions, is smaller cluster size. Whenever you store a file, it is stored in clusters. Unfortunately, if that file does not take up the entire cluster, the rest of that space is wasted. For example, if you have a cluster size of 32 KB, but your file is only 10 KB, 22 KB is wasted. The table below shows a detailed comparison of the cluster sizes of FAT16 versus FAT32.
 

Cluster sizes available under the most common file allocation tables.

NTFS
 NTFS should be used if you are only going to use the computer with Windows NT. It cannot be read by any other operating system except for some recent versions of UNIX. You can create your partitions as large as you like.

Ext2
 The Ext2 file system is generally only used for UNIX. In the Ext2 file system, you can have partitions as large as 4 terabytes. When you format your drive, you have the option of what cluster size you would like to use. Remember, smaller cluster sizes give you more storage room but can cause the system to be inefficient.

Formatting
 When you format your hard drive for DOS or Windows, first, don't forget to use the /s switch with the Format command, as in format /s. That switch tells the Format command to add the necessary system files for booting up. If you format under a Windows 95A or earlier, DOS, or a boot disk with a Windows 95A or DOS base, it automatically formats to FAT16.

If you format using a Windows 98 base, it formats to FAT32. If you format under NT, it gives you a choice of whether to use NTFS or FAT16 (or FAT32 if you are using Windows 2000). If you format under Linux, it defaults to the Ext2 file system, but it gives you a choice of what to use.

Installing a Hard Drive

Step 1: Select a hard drive
For most people, an 8.4 GB hard drive running at 5,600 RPM will do the job. Increasing the capacity obviously allows you to store more on the drive. Increasing the RPM (to either around 7,200 or 10,000 RPM) will make the drive run faster and can dramatically increase the performance of your computer.

The primary hard drives on the market today are UDMA 33, UDMA 66, and SCSI. Most of the lower- to mid-end hard drives are UDMA 33s. For most people this type of drive is fine. If you want greater performance, you can move to UDMA 66 or SCSI, which allow more data to be transferred at one time, but this comes at a price. Additionally, UDMA 66 only works as a primary hard drive for Windows 98, and your motherboard must support it.

Below we discuss the installation of a UDMA 33 or a UDMA 66 drive (IDE drives) as a secondary hard drive; however, most of the tips here will apply to installing it as a primary too.

Step 2: Back up
In most situations you will not lose any data if you are simply adding the hard drive as a second hard drive, but bad things can happen. You wouldn't want to chance losing that novel that you have been working on for the past three years would you? Back up your most important documents on floppy. If you have a tape or high-capacity drive you might opt to back up the entire contents of your hard drive.

Step 3: Installation
The first thing that you should do is take note of any numbers located on the label of the hard drive. You'll need to know the number of cylinders, heads, and sectors.

For any IDE-based hard drive, you should be concerned with:

  1. The IDE cable
  2. The power cable
  3. The drive itself

On the drive, there should be jumpers labeled "Master, Slave, and Cable Select (or CS)." If you are installing the drive as your primary hard drive, or if it has its own IDE cable, choose Master. Otherwise, select Slave. Cable Select sometimes works on newer motherboards that support it. This allows the mode to automatically be set by the computer, based on how it is positioned on the IDE cable.

The drive should easily mount (with the screws that came with the drive) in any of your 3-1/4" drive bays (the small ones). Many drives also come with mounting kits for 5-1/2" drive bays. Once you have the drive screwed in, it is time to attach the cables.

On the IDE cable, there should be three plugs. One plugs into the motherboard, one to a primary device, and one to a slave device. Hook up the cable based on what you chose when you set the jumper on the hard drive.

Make sure that you align pin 1 of the cable (indicated by a red line) with pin 1 of the connector on the hard drive. Note that sometimes only pin 2 is labeled on the hard drive. Pin 1 is in the same place as pin 2.

Now find an open power cable, and plug it into the drive. That's it! You're done with the physical installation. Close the computer case.

Step 4: Adjust the BIOS
Most of the time, the new BIOS will automatically detect and install the settings for your hard drive. If it does not, then the best thing to do is look in your computer's manual and find where the settings that you need to change are located. The numbers for those settings should be listed in your hard drive's manual.

Step 5: Format the drive
When you start Windows, it should start normally. It may show the "New Hardware Found" wizard, but most of the time, it will not. If you open up Windows Explorer, you should be able to see your new hard drive in the listings. In some cases, you may need to partition the new drive using fdisk. (The instructions should be found in the hard drive's manual.) The last thing you need to do is to format the drive. Find the drive in Windows Explorer, right-click on it, then click Format. Make sure you choose the correct drive, or you may end up erasing something important.

Step 6: Install your applications
Now you're ready to start installing your applications.

Hard Drive Interface Specifications

Interface Data Rate (MB/sec) Number of Devices
SCSI 5 8
Fast SCSI 10 8
Ultra SCSI 20 8
Wide Ultra SCSI 40 8
Ultra2 SCSI 40 8
Wide Ultra2 SCSI 80 16
Ultra2 SCSI 160 16
IDE/ATA 8.3 2
ATA-2 16.6 2
Ultra-ATA/33 33 2
Ultra-ATA/66 66 2
FireWire (1394) 50 62
USB 1.0 1.5 127

Source: www.techrepublic.com

Last Update: February 28, 2005
Yannis Grammatis