It’s always been important to make sure that your operating system winds up on the right storage drive, but this has become an even bigger issue with the creation of high-speed solid state drives.
Now you want to make sure that your operating system is on the drive that’s giving you peak performance, but these drives are expensive. PC builds often have expensive high-performance storage drives for the operating system and cheaper options for bulk storage. This leads us to the question: How do you make sure the operating system gets on the right drive?
The easiest way to tell which drive you’re installing your operating system on is to simply only have one drive connected during installation. You can also use drives with different storage capacities to pick the right one for your Windows operating system.
Alternatively, the most hands-off way of getting your operating system on the right drive is to install it, check your drives using the Disk Utility, and then install Windows again if it wound up on the wrong hard drive.
Whether this is your first PC build or your fifteenth, let’s find out how to get your operating system on the right drive.
Why Is It Hard To Identify Drives When Installing Windows?
If you’ve ever tried consistently tracking your drives by number, you’ll notice that Windows isn’t necessarily cooperative when it comes to ordering drives. This has to do with how Windows enumerates and the drives that are connected to the operating system.
Windows enumerates drives every time it boots. This doesn’t create a consistent relationship between drives and can in fact arbitrarily reassign different drives to different numbers. This is often the case when dual booting multiple operating systems with several unformatted storage drives attached.
The physical SATA and RAID channels that your drives are using don’t necessarily have a relationship with how Windows enumerates these drives. Your BIOS will keep a consistent enumeration for the drives, but Windows doesn’t seem concerned with picking up on that information.
This creates some problems when you’re looking into installing a new operating system or consistently using your drives by number, since you’ll just see the following on the install page:
Not very helpful if you need to install the OS onto a specific drive!
Why It’s Important To Know Which Drives You’re Using During Install
There’s a few important reasons why you need to know which drive is which during your installation. This has to do with drive speed, storage capacity, and the goals you have for your system.
Speed And Performance
The first reason it’s important to know how to tell the difference between drives, is the fact that not all drives are equal. SSDs are much faster than HDs, but the cost of storage on an SSD is still much higher than that on an old-school HD. This means a common setup is a smaller SSD with the operating system and a larger HD for file and program storage.
You need to be able to tell which drive is which in order to figure out which drive you’re installing your operating system on. This is important for maxing out the speed of your OS.
In my case, I went out and purchased two PCIe 4.0 NVMe SSD drives:
This was because I had a dual-PCIe4 SSD motherboard on order. However the motherboard kept getting delayed, so I ended up buying an alternate motherboard with one PCIe 3 slot and one PCIe 4 slot:
However PCIe 3 M.2 drives can run much slower than PCIe 4 drives, so I wanted to use the fastest slot for my Windows install.
Protect Important Files
Another reason to know which drive is which is that you’ll also need to tell the difference during install to protect those storage drives. If you’ve got files stored on one of those drives, they can get wiped out during the formatting required to install an operating system.
Here’s how you can safely, quickly, and reliably tell the difference between your drives during a Windows install.
How To Tell Which Drive Is Which
We’re going to start with the most simple solutions and work our way down to more complicated options. Being able to figure out which drive is which is not just useful for installing a new operating system, but it can help along the way when you’re using storage drives or looking to expand the storage in your PC.
Unplug All But One Drive
This first solution is by far the easiest. If you’re looking to protect your storage drives and you want to make sure that your operating system lines up on a particular SSD, all you need to do is unplug every drive but the one you want the operating system installed on.
This ensures that you have a no-risk scenario for installing your operating system onto your hard drive. With only one option to choose from, and we physically made sure that is the correct option, your files will be protected and your operating system will land on the correct drive.
This does come with one major downside. You need to install and format your other hard drives or SSDs after your operating system has been installed. This means opening up your computer case, physically connecting the drives, and then formatting them again once Windows boots up.
If taking an extra step during your installation and setup doesn’t sound like a big deal, this is by far the easiest and cleanest option for ensuring that your Windows operating system winds up on the right drive.
Use Drives With Different Storage Capacities
Windows might not have a way to cleanly enumerate drives, but it will always tell you the storage capacity of the drive you’re looking at.
This gives us a quick shortcut to figuring out which drive is which. We mentioned earlier that plenty of PC builds today feature a smaller SSD to house the operating system and a few programs, and a much larger hard drive for storage capacity. If this is the case for your set up, simply look for the smallest to drive and install your Windows operating system on that.
Of course, this method does involve buying drives with different storage capacities. Having two drives at the same storage capacity will cause Windows to lose the ability to distinguish between those drives when enumerating them. This means that a cutting edge 500 GB drive is going to look essentially identical to the clunkiest 500 GB hard drive you can find.
If you’ve got drives with different sizes, all you need to do is pick the one you want your operating system on ahead of time and remember its storage capacity when it comes time to install Windows.
Check The Order Of Your Drives In Your BIOS
The next method is a little risky, but it could wind up working out if you have a low risk set up situation.
The BIOS will always list the enumeration of your drives. What this means is that you can sometimes trust the order that BIOS places your drives in when installing a new operating system:
In the above case, the two NVMe drives are listed as:
I can then look these up in my motherboard’s manual or the “specification” page on the Asus website, and see that they mean:
- M.2_1: “(PCIE 4.0 x4 and SATA modes) storage devices support”
- M.2_2: “(PCIE 3.0 x4 and SATA modes) storage devices support”
Great, this means that the first drive to be listed should be the PCIe 4.0 one, and the second listed drive should be the PCIe 3.0 one.
Warning: Of course, Windows has its own protocols for enumerating drives. So we can’t guarantee that the Windows installer (or drive manager, later on) will list them in the exact same order.
In my case, they were in the same order (so I correctly installed to the PCIe 4.0 drive), but your experience may differ.
This is an all right option if you have a hard drive situation that was designed with some redundancy. If you’re building a PC with two 500 GB SSDs that are essentially identical, there’s no harm in just trusting Windows to agree with BIOS.
However, this is probably not worth the risk if you have a storage hard drive full of files you want to keep. Remember that the formatting and partitioning for installing an operating system requires you to wipe all data from a drive. This means losing the music, movies, and pictures you have on a hard drive if you accidentally select the wrong option.
Check The Physical Order Of Your Drives
Disk 0, 1, 2, and 3, all refer to the physical connections your storage drives take on your motherboard. These enumerations refer to their hardwired locations which might matter depending on your motherboard.
It’s pretty common for a motherboard to have a port designed for more modern, high-end drives and then several designed with generic storage in mind. It’s considered a best practice to install your operating system on the main port and then let the storage drives take up the rest.
The best time to get the physical order is during your installation. Windows tends to not like having drive locations changed. Operating systems use these port enumerations to decide where files go, execute programs, and otherwise run smoothly.
Check the documentation that came with your motherboard to find out which port is optimized for the drives you’re using. Getting this one right before your install is key for maxing out your PC’s performance.
Install Windows And Check With CrystalDiskInfo
Our last option is the most straightforward one, but it might not work for every user and every PC.
All you have to do is install Windows and then boot up your new operating system. Once things are up and running you’ve got a variety of tools you can use to find out which drive your operating system was installed on.
There are programs that come with Windows, like the Disk Utility, that can check the status of your drives, and third party programs like CrystalDiskInfo that present the information in an easier to read way.
If your Windows operating system got onto the right drive, then you’re good to go. If it turns out that it went up on the wrong hard drive, all you need to do is reconfigure and do a new installation.
For example, if you installed Windows onto the “C:” drive (which is typical) and you wanted to install it onto the PCIe 4.0 slot – like in my case – you would want to see the following:
The key thing here is the first part of the “Transfer Mode”. In this case, it’s good that it says “PCIe 4.0”. However if you see the below instead, that might be a bad thing:
In the above case, it’s saying that the drive is plugged into the “PCIe 3.0” slot – a bad thing in my case.
Note: The above screenshot also says “PCIe 4.0” and “Standard: NVM Express 1.4”. This means that the drive is capable of running at PCIe 4.0 speeds. But the key thing is the first part of the transfer mode, which says “PCIe 3.0” – that is what the drive is actually running at.
This approach involves a little bit of trial and error, but it’s a hands-off solution for individuals who aren’t as comfortable plugging and unplugging the drives on their computer. Plus re-installing an operating system can take as little as 15-20 minutes nowadays, due to super fast NVMe SSDs.
Handling all that expensive hardware and making sure that pins don’t get damaged can be a little hectic for first-time PC builders. This gives you a way of controlling which hard drive your operating system lines up on without needing you to potentially jeopardize expensive solid state drives.