Having multiple hard drives in your computer is a great thing. Knowing which Windows drives are on each physical hard drive is crucial, though, as subscriber Vernon from Australia figured out. Vernon wrote to ask:
I have Win 7 PRO with 3 x HDD (each 1Tb) C, D, & E. I wish to replace drives D & E respectively. How do I know physically which drive is D and which is E?
Vernon’s problem is an unusual one because many people only have one hard drive in their computers. That way, they miss this issue.
They also have all their eggs in one basket (all their files on one hard drive), so they better be doing their backups. As a friend of mine says "there are two types of hard drives, those that have failed and those that haven’t failed yet."
The answer to Vernon’s question depends upon several things that may be true, and will make the identification easier.
First, are all three drives the same brand and same size? If not, that will reduce the uncertainty.
Fortunately, from within Windows 7 (and earlier versions of Windows), we can determine the model number of the hard drives. This is because the drive manufacturers provide the model number in their firmware on the hard drive, and Windows reads it and makes it available to us.
In this first step, we open Windows Explorer (or My Computer, which will get you to the same point), and right-click on the drive we want to examine. In this case, Vernon wants to change his D and E hard drives, but not his C: drive – but he doesn’t know which logical drive (the “drive” recognized by Windows) is on which physical hard drive.
Once we right-click on the drive (let’s do D:, which I’ve named Data) in Windows Explorer, we select Properties from the pop-up context menu. That will open the "Data (D:) Properties" dialog box. Click to the Hardware tab and you’ll see all the physical drives on that computer.
The next step involves a guess as the starting point, if you have more than one hard drive. As you can see above, I have two physical hard drives (disk drives), an Hitachi drive and a Seagate drive.
I remember adding the Hitachi drive later, but setting my initial system up with the Seagate 1.5TB drive split into a C: and a D:.
So, I click on the entry for the ST31500341AS 1.5TB SATA3 hard drive. Then, click the Properties button at the bottom of the dialog box.
That opens the "ST314500341AS ATA Device Properties" dialog box. The General tab tells us that this drive is at Location 0 (Channel 0, Target 0, Lun0). Remembering that computers count by starting at 0 (not at 1), this is the #0 SATA connector on the motherboard (or #1, if the motherboard manufacturer started counting at 1).
The real benefit is on the Volumes tab – or should be there…
However, it’s blank. That’s not a lot of help. The key is the button near the bottom that says “Populate.”
This is where it gets tricky – there’s a bug in the code, apparently, at least in Windows 7 Ultimate (and probably in the other version, too). When I click this button, all it does is close the Device Properties dialog box.
The trick is to stay on the General Tab of the physical hard drive’s Device Properties dialog box, and to click the Change Settings button.
This opens up a similarly labelled and similar looking dialog box, EXCEPT that the new dialog box has another tab called "Policies."
If we click on the Volumes tab in this one, we can click on the Populate button..
..and it really worked. Now we can see the volumes (the drives that Windows recognizes and uses) that are stored on this physical hard drive.
We can see that this Seagate physical hard drive actually has three partitions (three volumes) that are recognized by Windows 7. One is used as C:, one has been named Data and is used by Windows as D:, and the other 100MB volume was set up by Windows 7 during the install process as a System Reserved volume.
OK, that solved the problem of learning which Windows drive is on which physical drive – or it does if the three drives have different manufacturers or different model numbers.
Suppose the drives are identical… what can you do?
That’s the time where you have to experiment. Make a note of some of the files and folders on each Windows drive.
Then, you will have to shut down Windows and the computer, pull the power plug, open the computer case and disconnect one drive. Then, insert the power plug, and start the computer.
IF the computer doesn’t boot (and says “Insert System Disk”) you know the disconnected drive is C:.
If the computer boots into Windows, open Windows Explorer and check the files available one a drive against the lists you made. That should tell you which drive is missing — D: or E:. Make a note of that.
If the drives are all the same manufacturer and model number, you might consider labeling them with a marker so that you can keep track of which is which.
Once you know which drive is which, consider renaming the Windows drive to reflect the manufacturer and model. Although you can see that I named my D: “Data”, I named my I: drive “Hitachi2TB” – that way, I always know, when I’m in Windows, which physical drive I’m using.
Vernon could name his, if they were all Hitachi 1TB drives with the same model number, something like Hit1TB1, Hit1TB2, and Hit1TB3. Windows will not allow anything but letters and numbers in the drive name.