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teddybear
13-02-2003, 12:17 AM
In plain English, whats the difference between the two drives?

mikebartnz
13-02-2003, 12:28 AM
Physical drives are separate drives whereas logical drives are several drives within one physical drive

Merlin
13-02-2003, 02:18 AM
A physical hard drives is exactly that - a physical unit that can be handled. It is also referred to as a hard drive or HDD (Hard Drive Device)


A logical drive is a subdivision of a physical hard drive and is created using a disk partitioning programme.

A logical drive is unique since it can only be used for storage - it cannot be bootable or active.
A logical drive can only exist within a specialised partition known as an extended partition.
A logical drive can only be created on a physical hard drive - not on a removable disk because of technical reasons.

teddybear
13-02-2003, 08:10 AM
Thanks for your replies.
Now I understand.
Using Win98 P4(1600)
As I have 2 Seagate HDDs - 1 as my Primary (New 40gig 7200rpm)
- 2 as a Secondary storage (10gig 5400rpm)
As I remember I formated No 2 as a storage only.
Used Seagates DiskWizard2002.
Is this the correct way?

Merlin
13-02-2003, 10:30 AM
You have the general gist of it though there is more.

Some of it relates to the design of the motherboard allowing for two channels (or connections).

Each channel (and they are called primary and secondary) connects to a device (the physical hard drive or a CD or a DVD or a Zip drive) by a cable. Each cable can have a maximum of 2 devices attached. They are referred to as the master and the slave. Who is master and who is slave is determined by small connections - known as jumpers - on the device. The device manufacturer supplies details on these 'settings'.

BIOS - basic input/output system - settings must be adjusted for additional or altered devices to be recognised by the computer and eventually the operating system. The motherboard manufacturer usually supplies instructions about this.



The next area is the 'generally agreed' area of partitioning.

Hard drive manufacturers as well as operating system designers loosely agree that a physical hard drive can be divided into a maximum of 4 main partitions. This relates to the physical design of the hard drive and has it's origins in the early days of computer design.

In the early days, production costs where extremely high. Space was expensive, hard drives small and so partitions where not needed. It wasn't till later when production costs dropped and inbuilt limitations with operating systems appeared that hard drive partitions became necessary. The space available to store the partition information on a hard drive was small. Without going further, there can only be a maximum of 4 main - or primary - partitions.

A primary partition is unique in that it can be bootable - or active. This allows an operating system - or at least the initial startup files - to be installed on a primary partition. There is more - search Google if interested.


One - and only one - primary partition can be changed into an extended DOS partition. The extended DOS partition is inaccessible in itself. It can contain a number of logical drives that can be accessed. Again there is more - search Google if interested.