How come my drives have different letters in dual boot environment?

[mattssi]

I have windows nt and windows 2000 dual boot. In NT, I have a C,D,E drive and F is my cd rom. In windows 2k, it shows C,D,F with E as the CD Rom...... Why would this happen?

Also, what makes a 'primary' partition, primary?

[mairving]

I would suspect that one of your partitions is FAT32 which NT can't see. You can tell how it is partitioned by going into My Computer/Right click on drive/look at File System. If it is it can be changed but not without a little grief. If it doesn't have an OS on the FAT32 partition, then you can move everything off of that partition. Then go into the Administrative Tools/Computer Management/Disk Management. You can delete that partition and create a new one with either FAT (2.1GB limit) or NTFS which NT can read.

As far as your other question about primary partitions. It varies from OS to OS. In Windows 95/98/ME, you tell it during fdisk. In NT & 2000, I don't know if you have the option to tell it. In Linux's fdisk, you tell it during fdisk also. You can have up to four primary partitions but only one extended partition.

[mattssi]

Well, I have the FAT partition for NT because, I couldn't do that any other way. And the other 2 partitions are NTFS. I can't figure out how to change it.

Also, I know how to set the primary partitions using G disk, but I'm just askin WHAT MAKES it a 'primary' partition? Is it just the first partition it looks to to boot?

[cobra]

you can change drive letters in NT and win2k and win9x. I would not recommend it if you have program pointers pointing to specific partitions. Although it can be done.
It's easier to change drive letters before installing programs on other partitions.

[mairving]

I copied this from Powerquest (makers of PartitionMagic). It is pretty informative. Link

We have found here at PowerQuest that many of our users are confused by the Extended partition and what it does. We have also found that many users are unsure of what type of partition they need--whether it be a Primary partition or a Logical partition. Hopefully we are able to provide a little insight that will help eliminate some of the confusion.

How did it all begin? Many years ago, when hard drives became common in computers, most hard drives were small and therefore limited. At this stage, though the drives were small, they were still considered to contain adequate space to carry us many years into the future. Well, we all know the story. As any computer user now knows, there never seems to be enough hard drive space. In the beginning, however, with one hundred to five hundred MB hard drives, it was believed that most users would never need any more than one partition, or division of the space on the drive. However, the governing powers at the time decided to build in a small provision for "power users" which would allow them to divide their drives into more than one partition. For this reason, a standard was developed that allowed for a "generous" four Primary partitions. It was soon discovered, however, with the development of larger hard drives and a variety of different operating systems, that four partitions would no longer be sufficient.

This insufficiency lead to the development of the Extended partition. The Extended partition, by nature, is a Primary partition. What then makes it different? The Extended partition was created in an attempt to overcome the four Primary limit. This is significant because inside the Extended partition more partitions called Logical partitions can be created. Logical partitions are so called because they are a logical chain of partitions that, when added together, equal the size of the Extended partition. One thing to note about the Extended partition is that it never receives a drive letter. One way to think of the Extended partition is as a container that goes around all of the Logical partitions. Although the Extended partition does not have a drive letter and does not contain information like the Primary partition and the Logical partition, it is still necessary to make modifications to it when attempting to move space from a Logical partition to a Primary partition or vice-versa.

Now that we know what each one of the partitions are, let's discuss what they do. We have found through a number of our own in-house tests and from many of our users that several of the most common operating systems such as Windows 95 and OS/2 have a problem working with multiple visible Primary partitions (MVP's). MVP's occur when two or more Primary partitions (up to four) are visible on a single drive at one time. Therefore, the rule of thumb states that there should only be one Primary partition visible (or assigned a drive letter) at any given time. This brings up several questions of how and when to use Primary partitions.

In general, Primary partitions should be used in conjunction with an operating system such as in a multi boot situation. In this case, one Primary partition would be active and bootable, and the other Primary partition containing the other operating system, would be hidden or not visible, and therefore not receive a drive letter. With this setup, PartitionMagic (or other programs such as System Commander by V-Communications, or OS/2's Boot Manager by IBM) would be used to set active the desired Primary partition for boot. It would also hide the remaining Primary partitions therefore only keeping one Primary partition visible at any given time.

Once the Primary partition has been created for the operating system, then Logical partitions can be created for programs and data. Remember, however, that before the Logical partition can be created, an Extended partition must be created. When the Extended partition is created using PartitionMagic, a blue outline is created surrounding free space (unformatted space that is not currently reserved or set up to store data). It is with this Free Space that Logical partitions can be created and allocated as desired.


[Edited by mairving on 03-04-2001 at 05:12 PM]

[glc]

With NT, you can change drive letters in Administrative tools - Disk Administrator. Change the CD to something like R: first - then you can sort the hard drives.