[packman]

I'm thinking of reorganising my hard drive(s) for dual-booting but am unsure as to whether what I propose will work. I'd be grateful for any useful comments.

I currently use Win2K on a hard disk that I've partitioned thus (all partitions here are NTFS):

C:Primary, bootable (Win2K)
D:Logical (used)
E:Logical (used)
F:Logical (used)

Attached to the same PC, I also use an external USB-connected hard drive that I've partitioned so as to give (again, NTFS):

G:Primary (used)
H:Primary (used)
I:Primary (used)

I plan to back up what I've got on D, E and F and then delete the Extended partition which they currently comprise. Partition C and its contents would remain untouched. I would then reconstruct D, E and F so as to make E a Primary partition. (D and F would be made into an Extended partition again). I would then install a copy of WinXP on to E. So thereafter, the booting option would be between Win2K and WinXP, both NTFS.

Would the presence of the USB drive constitute five primary partitions and therefore break the rule of having only a maximum of four Primary partitions? Or would the USB drive not count, for that rule?

I assume that, once I've installed WinXP into the E partition, I'll be able to boot up into C and, in the Startup & Recovery section of the Advanced tab of System Properties of Win2K, it'll be possible to configure the bootup sequence to initiate either Win2K or WinXP. Is this correct?

Can anyone see any potential problems with this proposal?

[jmmijo]

I was not aware of a limit of only (4)Four Primary Partitions but I suppose you can only try it and see if this works or not.

I can't see any issues in that you can always use the Disk Management tools in either Win 2k or XP to manually re-assign the drive letter except the partition you booted up into

[danleff]

The primary partition limit of 4 is for each physical hard drive. So, if you have no more than four primary partitions on each physical hard drive, there should be no problem.

[packman]

I see what you're saying danleff. Presumably, a USB drive doesn't count anyway, as far as that rule goes, because it's not an IDE-connected device?

[jmmijo]

Originally Posted By: danleff

The primary partition limit of 4 is for each physical hard drive. So, if you have no more than four primary partitions on each physical hard drive, there should be no problem.

Thanks for that bit of knowledge Danleff, this makes more sense to me so I will store this away for future reference

@packman, I would say try it on the external USB device and see what happens, it's possible that if you create more then (4)Four Primary partitions that the OS will only pick up the first 4 and none of the others.

[danleff]

I have never tried this with a USB connected drive, but I will let you know. I just happen to have one to try it on from my ole laptop.

Usually the partitioning software will complain about this and not allow the partitioning to continue. I just had this happen with gparted (Linux). I can try it on PartitionMagic 8 and let you all know.

[danleff]

I just tried it.

When you try to create more than four primary partitions in PartitionMagic, the ability to create any partitions is greyed-out. So it seems this applies to USB drives, as well, which are seen as any other physical drive. See this Microsoft article.

[jmmijo]

So I would say if you really need to create more then (4)Four Primary patitions on a single HD, then you have to create the remainder as an Extended partition/partitions instead

[danleff]

If you create an extended partition, then you create logical partitions (as many as you need and space permits) within the extended partition. I don't know if Windows likes this, but with Lnux I have multiple logical partitions within an extended with various distros on each logical partition.

[packman]

danleff,

I think you're missing an important factor here and that is that, by definition, the USB drive is an extra physical drive. Therefore, there's some question as to whether having two primaries on the main HD and, say, three primaries on the USB HD would overstep the limit. The real question, therefore,is whether you have to regard the USB drive as part-and-parcel of the main drive or not. The partitions you create on the USB HD certainly carry on, in terms of partition lettering.

[danleff]

Let me elaborate further. Here are the primary partitions on my system. I have;

A primary master drive with four primary partitions, the rest logical partitions on an extended.

A Primary slave with two primary partitions and multiple logical partitions inside the extended.

A sata drive with one primary partition and the rest on logical.

Another sata drive with one primary and the rest logical inside the extended.

I partitioned the USB drive with four primary partitions. When I tried to partition the fifth, the software greyed out the option of creating another primary partition on the USB drive.

Ditto on the primary master drive. More than four partitions are not allowed on each physical drive seen by PartitionMagic or gparted (the latter application in Linux).

All five drives are seen a separate physical drives in the partitioning software packages used.

[packman]

Thanks, that's interesting. You're using Partition Magic, though. The situation might be slightly different if dealing instead with DOS or Windows. In Win2K, for example, you can edit partitions in Windows Management and I can't help but wonder what Windows would do if I tried to beat the rule-of-4. Rather than preventing me from devising more than four primary partitions, spread across both main drive and USB drive, would it instead delete the C partition? I'd certainly hope not, but the fact is I just don't know.

Certainly, at the moment in Windows Explorer, my partitions C-thro'-I are not displayed as being on separate physical drives. Thus, I've no idea as to whether Windows is regarding my main drive plus USB drive as one, single hard drive.

D'ya see what I'm getting at?

Okay, you've been using Partition Magic but the scenario I'm describing is where I'd be installing WinXP into an existing but empty partition (on the main physical drive). The making of the additional primary partition for WinXP, and its formatting, would be done entirely within the WinXP Setup. It's hard to tell what the WinXP Setup would do, though, if it found I was asking for more primary partitions than the rules allow. It might decide instead to delete one of the existing primaries, in order to comply, in which case there'd be a risk that it'd delete the C partition!!!!

[danleff]

Take a look at this Microsoft Article. Look under the section "using basic disks" as the link would not allow me to point to that section directly.

Windows Explorer does not show what physical drives your partitions are on, only the apparent logical order in which Windows sees them...C...D...E...and so on.

Windows XP's Disk Management Utility will display the physical drives and their partitions, within Windows XP.

PartitionMagic is a Windows utility. If you looked at your drives in PartitionMagic, then you would also see the USB hard drive as a distinct hard drive, as your IDE or SATA drives are.

If you use the PartitionMagic Rescue floppy disks, it uses a DOS environment, as does Windows fdisk.

Qtparted, a Linux utility, has the same limitations of four primary partitions per actual physical drive.

[packman]

Thanks for that link. I've taken a look and, yes, I knew most of that already. But hey, thanks. Nice to see it laid out concisely by Microsoft.

Currently, I use Win2K and, again, am familiar with what you can do as regards Disk Management. I suspect that Win2K's and WinXP's Disk Management are identical.

In the dark and distant past, I had some experience with Partition Magic. It's interesting to learn that PM would show the main and USB drives as being distinct, separate ones.