Solved Can I change the numbers of disks?

Just successfully installed a third M.2 NVMe in System 1, and all is working beautifully. Only thing I don't like is that the BIOS decided to call the new disk Disk 0, and now my OS is on Disk 1. I know this doesn't make any difference to anything, BUT ... I'd like to change the number of the new Disk 0 to 1, and the number of the current Disk 1 to 0.

Former Disk 0 (now 1) is plugged directly in to the mobo. The other disks are mounted in PCIe adapters. I Don't know why BIOS decided to make the new M.2 Disk 0, but it did. I was surprised, because I assumed the mobo disk would take precedence over the PCIe disks. Yeah, I know what assume does.

I could, I suppose, switch the M.2s, but I'm not sure that would do what I want to do. I could, ofc, clone the OS disk to the new Disk 0 and convert the current disk 0 to the backup storage purpose it's intended to have. Problem with that approach is that current Disk 0 is 500 GB, and the OS disk, now Disk 1, is 250 GB. The cloning approach would be a great waste of space. The 250 is way more than I need for the W11 OS (C:) and all of my programs (D:).

Any ideas, other than "Leave well enough alone!"?

I've not worked with a motherboard yet that has more than one slot for an NVMe drive but the SATA drives take their numbering from the port on the board they are plugged into, e.g. Port 0 may show as drive 0 or 1, Port 1 as drive 1 or 2, etc. Perhaps NVMe would work the same?

I havent seen any documentation about nvme

The same logic doesn't apply. The PCIe slots don't have port numbers AFAIK. The current Disk 2 is in the PCI Express card slot (physical link width x16; negotiable link width x4, x1) and the new Disk 0 is in the PCI Express x16 graphics card slot. I don't need a graphics card.

I have only one NVMe port on my motherboard, accepts one of two sizes/lengths, has a 512GB drive, hold-down screws go where the 2 red dots are.

@Berton

Yep. I've only got the one, too. That's why I'm using PCIe slots to get two more faaaaast drives.

I copied a 17 GB file from one M.2 to the other today. Reported speeds above 3 GB/s, and finished before I could blink twice. THAT's what I was going for. Bye-bye 350 MB/s copying. Been nice knowing you.

That is the way nvme drives work. I had an optane nvme as drive 0 and normal nvme data drive as drive 1.

I had some issues with optabe drive and replaced it with a normal nvme drive (cloned) expecting it to be drive 1.

To my surprise drive 0 and drive 1 were swapped around.

I had to physically swap drives around to make OS drive drive 0.

So I concluded drive numbers are allocated during boot i.e. not actual physical slots.

I have no idea why numbers switched but on reading articles, this is common.

So switching discs will probably solve your issue.

I added a WD 2TB SATA HDD drive to my desktop and no change in drive assignment, first time I ever saw the power and data cables already available in a case.

@Wisewiz

Short version...

NVMe drives pick their own drive numbers.


Or, you could just go to Home Depot and get a permanent marker and write whatever drive number you want, right on the screen where Disk Management opens.

Berton said:

I added a WD 2TB SATA HDD drive to my desktop and no change in drive assignment, first time I ever saw the power and data cables already available in a case.

Click to expand...

SATA drives use fixed physical SATA ports. NVME drives use a different pcie bus and drive numbers are logical rather than physical.

@cereberus

Thank you for that input. I believe you're right, but here's my problem if I go the route of switching disks:

I've got a heat sink attached to the NVMe that's on the mobo. That's no problem. I could, in fact, move that to either of my PCIe cards. BUT, and it's a big butt, err, but, I've got heat sinks fastened to each of the ones on PCIe cards, and they won't be moveable to the mobo with those heat sinks. I'd have to remove the heat sink from the one I moved. I don't like that idea one whit, because those things are STUCK on the chips on the NVMes. Wait, I think I'lll have to think this out again [Oliver, the musical]! Maybe there's a way. Hmmmm.

No way of manually controlling drive # assignment that I am aware of. It's dependent on the mobo and the drive configurations it allows. In my case, if only one m.2 slot used, it's disk 0. If 2 x m.2 used assigned disk 0 & 1. If a drive is then connected to a sata port, it becomes 0 and the 2 x m.2 drives become 1 & 2.

I have a Z790 with 4 NVMe drives and one Sata drive. The Sata drive is Disk 0. The others are boot drive Disk 1, then Disk 2, Disk 3 and Disk 4. I am not sure how the NVMe drives are ordered however. The PCIe lanes for the M.2 slots come from either the CPU lanes or the Chipset lanes.

@glasskuter

You always have a way of getting me thinking in new directions. Thank you for that input. Since I've got three NVMes now, and two of them are possibly switchable, I'm going to give some CAREFUL thought to doing this. I'm thinking I could maybe switch the disk on the mobo with the disk on the PCI Express card slot (physical link width x16; negotiable link width x4, x1), and then switch the card in the latter slot with the one in the PCI Express x16 graphics card slot. Whether that would give me the desired output remains to be seen, but I think it'll be easy to try, and if it doesn't work the way I want it to, I can go back to any of the physical arrangements of disks before the switching. Watch out, BIOS. Here I come! (Well, maybe.)

It's the new installation in the graphics slot that isn't moveable. I mean, that one's ATTACHED now. So, playing the move-a-moveable-drive and move-a-moveable-card game is doable. Maybe.

BamaInArk said:

I am not sure how the NVMe drives are ordered however. The PCIe lanes for the M.2 slots come from either the CPU lanes or the Chipset lanes.

Click to expand...

Yeah, that's a finger right on the problem: I don't know how the NVMe drives are ordered. Ideas abound, however.

I don't know why, but when I use my Windows 11 Pro on my M.2 PCIe adapter card, and plug in my SATA drive with Windows 10 on it, it corrupts my Windows 11 M.2 drive, go figure!

Is it possible the mobo picks the fastest drive as the main drive? Just a wild guess.

Wisewiz said:

@cereberus

Thank you for that input. I believe you're right, but here's my problem if I go the route of switching disks:

I've got a heat sink attached to the NVMe that's on the mobo. That's no problem. I could, in fact, move that to either of my PCIe cards. BUT, and it's a big butt, err, but, I've got heat sinks fastened to each of the ones on PCIe cards, and they won't be moveable to the mobo with those heat sinks. I'd have to remove the heat sink from the one I moved. I don't like that idea one whit, because those things are STUCK on the chips on the NVMes. Wait, I think I'lll have to think this out again [Oliver, the musical]! Maybe there's a way. Hmmmm.

Click to expand...

Well in the end, the drive number is meaningless really.

The reason I swapped my drives was simply because I have some batchfiles that use diskpart commands, and would have had to edit them all.

If you cannot physically move them around, I guess there is nothing you can do but live with the assigned numbers.

Q: Can I change the numbers of disks?

A: Yes. Just take a few out and throw them away.

That's it. The answer. I've always wanted a single-disk PC. That's why when I look at pre-built notebooks in a store, I always ask the clerk whether I can add a disk or disks, and whether I can expand the memory. It comes as no suprise to me that most of them have no effing idea, and have to seek a manager-type, who probably doesn't know either.