As you get into more niche computer builds, the specifications of each part matter more than just slapping together a build that can stream moves and run games. The type of hard drive you get is an excellent example of this.
While most people know that choosing an SSD will give you faster load times than an HDD, even some experienced builders have never heard of a CMR or SMR drive. Knowing the difference might help you squeeze more performance out of your build.
What is a CMR Drive?
CMR stands for conventional magnetic recording. It was the original standard type of drive before SMR drives were introduced.
CMR drives have a format where the plates that store the information are lined up next to each other. They fit together without any overlapping parts and often include a bit of space between each plate in case a track is registered incorrectly.
The read and write heads move to the information required and use it, then move to the next area on the hard drive with the required data. Each track is completely separate from the others, like they’re lined up in a queue. Because each track is laid down before the next with space between them, the read and write heads only have to be as large as each individual track.
Pros of CMR Drives
CMR drives are better for most users because they’re quick and inexpensive. They perform better for most tasks than SMR drives at this time.
- CMR drives have faster write speeds than SMR drives. When you’re doing something like gaming with a lot of data access and write operations, you’ll get better performance with a CMR drive than with an SMR drive.
- CMR drives are more suitable for holding the operating system or almost any other active program on the computer. Since they offer much faster performance than SMR drives, almost any program you actively use will work better with a CMR drive.
Cons of CMR Drives
CMR drives aren’t perfect. For certain situations, they aren’t going to work as well as SMR drives.
- CMR drives can’t hold as much information as SMR drives. Because of the track structure, there’s more wasted space in the design. Each area that can’t be used to write data reduces the drive’s storage capacity.
- Some users say CMR drives are more prone to failure. However, others argue that CMR drives are more reliable. It can be hard to determine whether problems people have with either drive are due to the type of storage or another issue.
These drawbacks aside, they’re great drives for anyone doing fast-paced computing.
Remember that potentially being more prone to failure doesn’t make CMR drives likely to fail. All drives have some chance of failure, but few people actually experience hard drive failure within the warranty period.
What is an SMR Drive?
SMR stands for shingled magnetic recording. It’s a newer technology that offers some benefits and some drawbacks over CMR.
SMR drives don’t place their tracks next to each other. Instead, data is written to a track, and then another track overlaps it. Each track is positioned in a shingled formation, almost like the roof of a house. This lets the disk hold much more data.
The write head on an SMR drive is larger than that on a CMR drive. It’s large enough to write a single track of data and then some. When it’s done recording data to a track, it moves over to start writing the next part of the data. However, it doesn’t move all the way away from the original track. The wider head causes it to overlap, creating the shingle effect.
Shingled tracks of data are held apart from each other in different zones. These zones let the disk update the information and help prevent accidental overwriting.
Pros of SMR Drives
The benefits of SMR are great for enterprise users or those who just need a lot of space to store data.
- SMR stores its data in a way that lets it hold much more information. Very large disks are often SMR rather than CMR because of this. If you have a lot of media files or storage that you aren’t accessing constantly, an SMR drive might be better for you.
- SMR drives are more reliable than CMR drives. They appear to be less likely to fail. This can be a huge selling point for people saving information to storage drives or enterprise users.
- SMR drives are more energy efficient. If you’re archiving data for storage, you might save a bit on your power consumption by choosing SMR.
Cons of SMR Drives
The cons of SMR drives can be a problem for users looking for a fast, performance-driven disk. However, they’re very useful for some users.
- Some say that SMR drives are more expensive, but they don’t always seem to be more costly. Much of the cost difference comes down to other specs, like speed, storage, and manufacturer.
- Information has to be written in a sequential manner on SMR drives, which means that any changes to a particular zone of tracks require rewriting the whole zone. This is another reason that SMR drives have such slow write speeds. Some say that this style of data management can increase the probability of your data being corrupted.
If you’re using an SMR drive for storage, neither of these is of any real concern. Files you save shouldn’t have to be updated regularly if they aren’t accessed and changed regularly.
How Do CMR and SMR Hold Data Differently?
CMR holds each piece of data in separate tracks, like a line of bricks built next to each other. SMR holds data in shingles that overlap, like roof shingles. That’s how they’re able to store more data on the drive.
Should I Use CMR or SMR for this Build?
If you still aren’t sure whether to use CMR or SMR, consider the following scenarios.
- A gamer who wants to install frequently played titles on a hard drive should look for a CMR drive. It will be quick enough that it’s less likely to slow down performance and introduce more lag into the game.
- A user who needs a place to store and save personal files for the future could use an SMR drive. The extra storage capacity and peace of mind that comes from knowing the drive is less likely to experience failure can be a real asset. Also, since the data isn’t accessed as frequently, the write times matter less.
- Someone making a budget build may want to go for a CMR drive. The performance and price point are very useful because the drive could work to run games or other operations with high write speeds down the line if necessary.
- RAID users should go for CMR disks. Using SMR can actually make your entire array less secure and more prone to data loss.
If you still aren’t sure, choose a CMR drive. Their benefits outweigh the drawbacks, and they are the more flexible and all-around option.
How to Tell Whether a Drive is CMR or SMR?
Unfortunately, a lot of companies don’t include whether the drive is CMR or SMR on the packaging. It isn’t one of the commonly expected pieces of information that all manufacturers have. However, there are a few signs you can watch out for.
- Check out the cache size on the drive. SMR drives often have a larger cache to try and mitigate their issues with speed. A drive with a 256 MB cache is more likely to be an SMR drive. If it has a 64 MB cache, it may be a CMR drive.
- You can look up the product codes for the drive you’re considering buying. You may find more detailed information about what you want to get. Online discussions about different drives sometimes also include more information about their specifications and how they’re made.
- Reach out to the company. Even on enthusiast message boards and discussion posts, the topic of how to identify a drive as SMR or CMR is not entirely resolved. The best way to do it is to reach out to the manufacturer you want to purchase a drive from. Ask whether your intended drive is the type you want and consider asking for a recommendation if it isn’t.
Before purchasing a drive, refresh the information you’ve learned. Manufacturers change their processes and parts regularly. You don’t want to buy what you expect is a performance drive and end up with a storage drive instead.
Frequently Asked Questions
Are SMR Drives Good for Storage?
SMR drives are great for storage, as long as you aren’t planning to access the data regularly. (For example, you may not want to store an active program you frequently use on an SMR drive.) Their reliability and space make them a good choice for archiving data.
Do Seagate Drives Use SMR?
Seagate uses SMR and CMR technologies like other companies, depending on the drive and product line. Reach out to the company with specific questions before purchase if they don’t include the information on the product data sheet.
Can SMR Drives Be Used with RAID?
You can use SMR drives with RAID, though it might not be the optimal choice. However, ensure all the drives you have use the same technology. No matter which you choose, stick with a single type of drive.