Problem with Drive letter assignment.

[Dinosaur]

Windows 98SE running on ASUS A7V133 Motherboard with 1000MHz Athlon CPU.

I am having problems with drive letter assignments. My current system is running okay with three new 40GB hard disks. It used to have three 20GB disks. The three 20GB disks are identical (as far as I can tell) Western Digital Caviar WD200BB disks, bought at the same time from the same dealer.

I am intending to install the 20GB disks on my second system, replacing the smaller disks on that system used by my girlfriend.

I removed the third 40GB Disk from my system and have been using that IDE port to work with the 20GB disks prior to installing them on the other system. The first two disks (40GB each) have one primary partition and several logical drives in extended partitions. Before replacing the third disk, the drive letter assignments were C, D, & E to primary partitions on disks 1, 2, & 3 respectively. Letters F up were assigned to logical drives in extended partitions.

I ran Fdisk from a DOS Prompt to delete the original partitions on a 20GB disk. I then used Fdisk to create a 6GB Primary partition. The remaining space was assigned to an Extended partition and one logical drive was created in the extended partition. The new partitions were formatted and scandisk was run. Some data was copied to the disk as further verification.

I did the above to all three 20GB disks. One of the disks had Drive letter E assigned to the primary partition on the 20GB third disk, which is what I expected. The other two disks had drive letter L assigned to the primary partition, with letter E assigned to a logical drive on the first disk.

Partition Magic 6.0 thinks that Drive letter E is always assigned to the primary partition on the third disk, disagreeing with the Windows 98SE assignments for two of the three disks.

As far as I can tell, I performed the same operations on each of the three disks in the same sequence, but got different drive letter assignments.

Does anybody here have any ideas on the above? I thought I knew how letters were assigned, and this was unexpected.

I want to understand what is happening before I install these disks on my second system. If I get strange drive letter assignments, a lot of the software on that system will not run. I intend to use a Drive Image utility to copy all the software, including the boot sector and the OS.

[JUAN DOS]

Dinosaur,
Primary partition drive letters are assigned prior to logical partition assignments. Have you checked using fdisk / drive info, to see what it says?

I intend to use a Drive Image utility to copy all the software, including the boot sector and the OS.

Unless these two PCs are identical, or nearly so, you will have little luck with the swap. Few have made it work.

[Dinosaur]

Juan DOS: I am familiar with the algorithm for drive letter assignment. With one primary on each disk, the primaries get C, D, E . . For Disks 0, 1, 2 respectively. Logical drives in extended partitions get the remaining letters in order, with the first disk getting the first set of numbers if it has more than one logical drive.

For my main system, the assignments are as follows for my 40GB disks.

1st disk: C (Primary), F, G , H, I
2nd disk: D (Primary), J, K, L
3rd disk: E (Primary), M, N, O

The above is just what I would expect.

When I replaced, my third disk with 20GB disks with one Primary and one logical, I got the following for one of the disks (as expected).

1st disk: C (Primary), F, G , H, I
2nd disk: D (Primary), J, K, L
3rd disk: E (Primary), M

For the other two disks, I got the following unexpected assignments..

1st disk: C (Primary), E, F, G , H
2nd disk: D (Primary), I, J, K
3rd disk: L (Primary) & M

Fdisk from a DOS Prompt and Windows Explorer agreed with the above, while Partition Magic showed the expected assignments for all three disks.

Since the three 20GB disks are the same type and size from Western Digital, I do not think that some subtle difference in the disks is responsible. It has to be some subtle difference in the sequence of events during installation of the disks and the use of the Fdisk & Format utilities.

I just cannot imagine what caused the strange assignments, especially since PowerQuest Partition Magic displayed the expected assignments for all three disks.

When you said that I would have trouble using drive images to move my OS and data to new disks, you were probably thinking about using images to move an OS and data from an existing system to one with a new Motherboard, new CPU, and new peripherals. This is a complicated job. It can sometimes be done by removing all the drivers before making images of the partitions. Drive Image from PowerQuest will run from bootable diskettes, allowing you to make images of the OS after removing all the drivers. When the OS comes up on the new system, you install the drivers required by the new hardware. I have seen this scenario work, and I have seen it fail.

I see no reason to expect trouble replacing the three disks on my second system with three 20GB disks. The three disks on the current system are only 12GB, 6GB, & 6GB, with some space unused in each partition. There will be no problem fitting all partitions from first two disks onto one 20GB disk. After copying all the partitions from that 20GB to the first two 20GB disks, there will be plenty of space to make images of the partitions on the 6GB third disk from the original system.

If I do not have drive assignment or other problems with the 20GB disks, I expect a Drive Imaging plan to work. I have used the PowerQuest Drive Image utility many times to do upgrades to larger faster disks for myself, for friends, and for clients.

[CuratoR]

For the other two disks, I got the following unexpected assignments..
1st disk: C (Primary), E, F, G , H
2nd disk: D (Primary), I, J, K
3rd disk: L (Primary) & M

Looks like both the partitions in the third disk are logical and no primary partition exists. Primary partiton is mapped first and then only logical. If there are three HDD's, C is given to the primary partition of the first HDD from which the system boots. D is given to another primary partiton from 2nd drive, E is given to another primary partition that is from third drive, then F,G,H,I is given to logical partitions from the first drive. J,K,L is given to logical partitions from the 2nd drive. M is given to the logical partition from the third drive. In ur case, it suggests that there is no primary partition in the third HDD, there are two logical partitions so it is mapped last.
The HDD from which the system boots, is considered as 1st. Then the primary master is considered as 2nd. Then the Primary slave is considered as third. Then the secondary master is considered as the 4th. Then the secondary slave is considered as fifth. The HDD from which the system boots is on one of the four position so the last line must be understood wisely becuz i've mentioned the secondary slave as fifth. There can be no fifth IDE Storage device.

I did the above to all three 20GB disks. One of the disks had Drive letter E assigned to the primary partition on the 20GB third disk, which is what I expected. The other two disks had drive letter L assigned to the primary partition, with letter E assigned to a logical drive on the first disk.

Either u are confused or ur os has gone crazy.
I've got three HDD's, and partitions somewhat similar to urs. One Primary partition on each HDD and 4,3,2 extended partitons respectively.
But Drive letter mapping is as expected. C,D,E to each primary partitions on the three drives and F,G,H,I J,K L respectivley to logicals on the three.

[JUAN DOS]

Dinosaur,
For your tenacity, you receive my utmost admiration.
I use Powerquest tools frequently. From my own prospective, it is faster to clean install OS and programs when setting up a new system. That is just my circumstances. We run few programs, so two hours and finito.

Looks like both the partitions in the third disk are logical and no primary partition exists.

CuratoR’s statement appears to be if not fact, at least how your setup is being recognized. I presumed the same thing, given your first post. If fdisk shows “L” as a primary partition, then I’m out of ideas.

You have more experience than I have, so good luck with the project.

[Dinosaur]

Strange as it seems, the primary partition on two of my three disks is not assigned letter E when instaled as the third disk.

BTW: Logical drives are always in Extended partitions. When Fdisk is queried for partition data, it shows An Extemded partition as an Extended Primary and asks if you want to see the logical drives contained in it. The user can never mistake a logical for a Primary.

Either Windows 98SE is misbehaving or something about the geometry of these two disks is causing the problem.

I just installed the third disk, and E is assigned to the primary partition as expected. I am going to check with Western Digital Tech support. Maybe they have heard of this problem.