You might consider installing some of your programs on D: (or whatever another drive might be named) instead of C:.

This doesn’t eliminate the chance of buying a replacement or second drive, but there are aspects of space management that can help reduce the frequency of problems, not to mention the simple value of knowing more. Personally, I no longer ever try to get by with a single drive in any system. There are advantages to multi-drive systems that a larger drive won’t always address. And I also routinely partition my first drive as well.

I tend to buy cheap disks (liquidation sites, etc.). The reliability is questionable for individual ones, but I also almost always buy an extra one as a spare. I now always have a few extras on hand. Cheap prices make extras feasible on a budget.

As far as terabyte sizes go, though, if you’re surviving with 4 9GB partitions today, I have no idea what you’d do with a 1 TB drive. You can clearly get by with 40GB, 80GB or similar smaller drives as secondaries and probably never miss the extra 900GB.

First thing you should do is learn the basic reasons why you’re seeing new files on your C: drive so much, then change whatever is causing it. Next, if your PC can accept a secondary drive (some can’t), then buy a couple that are reasonably priced and sized for your needs and learn how to plug one in and how to access and use it. (You might put it immediately to use initially just as a daily or weekly receiver for backups of your 4 partitions. You might also install a backup OS on it for emergencies.)

At that point, you’ve spent as little as possible, you’ve learned some fundamentals about file/space management, you have a system with more than twice the disk space you started with, you have backups, you possibly have a second OS copy to boot with and, hopefully, you have a spare drive that might be ready for use.

That might be a good time to replace your current 4-partition drive with your spare and perhaps turn that original into a new spare. Well, maybe.

What happens at that point can be a lot of things. The bits of knowledge and experience that got you there make it unpredictable. So many options open up, it’s no telling where it goes. (For me, it jumped to building my own PCs…)

Tom

It’s recommended to backup important data before resizing partitions, as there is always a small risk involved.

But I agree with Mrdenny, you can buy a much bigger disk without spending too much money.