Q&A: Is it safe (and wise) to span two hard drives to make one larger drive?

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Question from Carl: I read here that you can “span” (i.e. combine) multiple hard drives and use them as one large drive and access them all with a single drive letter.

I have a used, but working 1TB hard drive at home that I could install in my Windows 11 desktop computer to span with the 1TB drive that’s already in it to effectively give me a 2TB drive. (There is an open drive bay to install the second drive.)

Would you mind answering a question about drive spanning for me?

I happened to be in Best Buy the other day and I asked one of the Geek Squad techs if they could span the two hard drives into one for me.

His answer was they could but they didn’t recommend spanning drives because it’s actually better to just install a new 2TB drive and be done with it. He said spanning drives can also be risky.

Was he telling the truth or was he just trying to sell me a new hard drive? Frankly, I trust your advice more than I trust his.

Rick’s answer: Carl, it’s certainly true that you could install the 1GB drive in your desktop computer and span the two hard drives together to create one large logical drive that would effectively become one much larger C: drive.

While spanning drives isn’t actually risky if it’s done properly and you have a good backup routine in place, I’m afraid I have to agree with Geek Squad tech on this one. I do believe he gave you good advice.

This is what I recommend that you do:

1 – Purchase a new 2TB hard drive (or even better, a 2TB SSD).

2 – Install the new drive into the open drive bay in your computer.

3 – Download Clonezilla and use it to clone the contents of the old hard drive onto the new one.

4 – Change the boot order to force the PC to boot from the new drive, then format the original 1TB drive to free up all of its storage space. (If you need instructions for changing the boot order of the drives just send me the brand/model of your computer and I’ll be glad to help.)

The advantage of the above procedure is you’ll now have a total of 3TB of storage, but your all-important boot drive will be brand new (and therefore more reliable long-term). What’s more, if you installed a new SSD instead of a new hard drive your computing experience will enjoy a very nice speed boost as well.

Now all of the above being said, if you really want to span your two existing drives I’ll be happy to send you instructions for doing that. But again, I recommend that you not do it.

Bonus tip: Get yourself one of these awesome docking stations and you won’t even have to use Clonezilla to clone the drive. You’ll be able to initiate the cloning process simply by pressing a button! And as a bonus, when you’re done you can plug your spare 1TB drive into it and give yourself 1TB of additional overall storage (for 4 TB total).