Setting or Resetting Drive Number in a New Install

I just finished the first initial install of Win7 Ultimate 64x on a new build (no drivers just yet). I installed the OS on a 128GB Samsung 840 PRO SSD while it was the only drive in the case. I didn't pay attention to the drive number when I checked it in Drive Management. I connected the second drive (new 2TB WD Black: E:/) that I had preformated on another machine. When I checked in Disk Management, I found the C:/ drive number was 1 and the E:/ drive number was 0. When I connected the third drive (slightly used 2TB WD Black: F:/) from my XP machine (I eliminated the C: partition and expanded the F:/ partition on another machine) and it was numbered disk 2.

Why on earth did the C:/ drive get numbered disk 1 when it was the only drive on the machine and, when I added the E:/ drive, it got numbered drive 0? Is there anyway to switch the two numbers? I don't have a problem with doing another clean install if necessary if that would work.

That most often has to do with the SATA port you plug the HD or SSD into. You can try swapping them around so the OS drive is Disk0 so that if repairs are done it won't derail the System boot files to another preceding HD partition.

You may have been advised to plug the SSD into a certain port which is optimal but won't register as Disk0. I'd just leave it in that case being careful that only the SSD is plugged in during reinstall or Startup Repairs.

Sometimes you can't control which Disk# is assigned no matter where you plug HD. This was explained in an older thread which I saw earlier today so I'll try to find it. Someone else may chime in with knowledge of the exception.

The board I'm using (ASUS P9X79 WS) requires booting from one of the two Intel SATA 6.0gb/s ports (both if running two boot drives in RAID 0; I'm keeping the other port reserved in case I decide to do so someday). I moved the C:/ from the port that I was using to the other one and disconnected the two HDDs. When I fired the machine back up and checked in Disk Management, it was showing the SSD as being Drive 0. But when I connected the E:/ drive and fired the machine back up (I shut it down and kill the power before working inside), the C:/ drive was Drive 1 and the E:/ was Drive 0 (mutter, mutter, mumble, mumble).

The board also has two SATA 6.0gb/s ports running off a Marvel chip and four SATA 3.0gb/s running off the CPU. I have the E:/ drive running off one of the Marvel ports and I'm keeping the other Marvel port available for possible future caching of the E:/ drive (the board is set up for that). I was temporarily running F:/ on one of the Intel SATA 3.0gb/s but I didn't reconnect it this time (I'll eventually be running it off a LSI SATA/SAS 9211-8i SATA card).

I know I'm being totally anal (in my case, it comes with having ADHD) but it would be so much more convenient if Drive numbers 1-? (I have room for six) would correspond to the physical drive ID numbers and position in the case.

Thanks, guys. Oh well. It's annoying but it's not worth losing sleep over (said the old lady at 1 AM).

VistaKing said:

The first disk will always be Disk 0 unless there is an IDE drive then the second disk will be disk 1 and so on .

Did you install the SSD to SATA6G_1 and the other Drive to SATA6G_2 ?

No. I first had the SSD connected to SATA6G_2 (it was physically more convenient), then tried it in SATA6G_1 (I'm reserving SATA6G_2 for possibly running two SSDs in RAID 0 for the boot drive sometime in the future). I put the first HDD (E:/) in the SATA6G-E1 after I had installed the OS, then tried it in SATA6G_E2 (I'm reserving the SATA6G_E2 for possibly using an SSD for caching E:/ sometime in the future; it depends a lot on if I ever need the sixth HHD bay or not). When I added the second HDD (F:/), I put it in in one of the SATA3G_? (I'm not sure which one it is since it's there only temporarily until I get the LSI 9211-8i card (it and the breakout cables should be delivered Wednesday); I just wanted to check to see if it would show up alright.

VistaKing said:

The first disk will always be Disk 0 unless there is an IDE drive then the second disk will be disk 1 and so on .

Did you install the SSD to SATA6G_1 and the other Drive to SATA6G_2 ?

Not always.

Disk drive numbers may not correspond as expected to the SATA channel numbers when you install Windows on a computer that has multiple SATA or RAID disks

Microsoft said:

When you set up one of the operating systems that are listed in the "Symptoms" section on a computer that has multiple hard disks, you expect the disk assignment numbers to match the corresponding SATA or RAID channel numbers. If you experience mismatched channel assignments, you may set up the operating system on the wrong drive, or you may try to format the incorrect drive partition. Therefore, you may lose important data.

Additionally, when you install Windows Server 2012, Windows Server 2008 R2, Windows 8, or Windows 7, the installation creates a system partition alongside the Windows partition by default. The system partition is created to accommodate a Bitlocker requirement. Bitlocker requires that the boot files and Windows files are located on separate partitions. If the preselected default hard disk is not changed, the system partition is created on the disk that is detected as Disk 0.