What Makes Ssd Better Than Hdd

By | 11/11/2022

What’s the difference betwixt SSDs and HDDs? Solid state drives and hard disk drives are similar in their physical specifications, but they store data very differently. At that place are advantages and disadvantages to each type of drive, and deciding on which type is right for you comes downwardly to how you use your estimator. Our guide to HDD vs. SSD shows you how each type of storage drive works and what it means for yous.

What is a HDD?

The applied science backside hard disk drive drives is well known and well tested. Hard disk drives have been effectually for more than fifty years, steadily increasing their storage capacity and decreasing their physical size. HDDs rely on spinning disks, or platters, to read and write information.

hard drive

How hard disk drives (HDD) piece of work

Hd drives consist of 1 or more magnetically sensitive platters, an actuator arm with a read/write head on it for each platter, and a motor to spin the platters and move the artillery. There is also an I/O controller and firmware that tells the hardware what to exercise and communicates with the balance of the system.

Each platter is organized into concentric circles called tracks. Tracks are divided into logical units called sectors. Each track and sector number results in a unique address that can exist used to organize and locate data. Data is written to the nearest bachelor surface area. In that location is an algorithm that processes the data before information technology’s written, allowing the firmware to detect and right errors.

The platters spin at pre-set speeds (4200 rpm to 7200 rpm for consumer computers). Those speeds correlate to read/write rates. The higher the pre-fix speed, the faster a hard drive will exist able to read and write data.

Reading and writing

Each time y’all ask your figurer to retrieve or update data, the I/O controller tells the actuator arm where that data is located, and the read/write head gathers the data by reading the presence or absenteeism of a charge in each address. If the asking was to update the data, the read/write head changes the charge on the affected track and sector.

The time it takes for the platter to spin and the actuator arm to find the correct track and sector is known as latency.


The drawbacks to HDDs are a result of the mechanical parts used to read and write data, as physically finding and retrieving information takes more time than electronically finding and retrieving data. The mechanical parts tin can skip or fifty-fifty fail if they are handled roughly or dropped. This is a concern in laptops, but not as much in desktops. HDDs are too heavier and employ more energy than comparable SSDs.

Benefits of a HDD

The benefits of a hd drivs are that they are a proven technology, and are frequently less expensive than a solid state drives for the same corporeality of storage. Currently, HDDs are also bachelor with more storage space than SSDs.

What is an SSD?

Solid land drives use flash memory to deliver superior operation and durability. Because there are lots of modest, moving parts inside your hard drive — magnetic heads, spindles, and spinning platters — it’s easy for things to go incorrect and you could lose your important data. Without moving parts, SSDs are more durable, run cooler and apply less energy.

Crucial solid state drive and motherboard

How solid state drives (SDDs) work

SSDs can exist thought of as large USB drives; they utilise the same base applied science. NAND, the engineering in solid state drives, is a type of wink memory. At the everyman level, floating gate transistors record a charge (or lack of a accuse) to shop data. The gates are organized in a grid pattern, which is further organized into a block. Block size can vary, but each row that makes upward the grid is called a page.

An SSD controller performs several functions, including keeping rail of where data is located.

Reading and writing

Updating data is more complex for SSDs. All the data in a block must be refreshed when any portion of it is updated. The data on the former block is copied to a different block, the block is erased, and the data is rewritten with the changes to a new block.

Each time you enquire your reckoner to retrieve or update data, the SSD controller looks at the address of the information requested and reads the accuse status.

When the bulldoze is idle, a process called garbage collection goes through and makes sure the information in the quondam block is erased and that the block is complimentary to be written to once more.

There is another process called TRIM that informs the SSD that it tin skip rewriting sure data when it erases blocks. Considering there are a finite number of times any block can be rewritten, this is an important process that prevents premature wear on the storage drive.

To further prevent article of clothing on the drive, there is an algorithm to make certain that each block in the drive gets an equal corporeality of read/write processes. This process is called wearable leveling and happens automatically as the bulldoze is working.

Because the read/write process requires data motility, SSDs are usually overprovisioned with storage; at that place is always a sure amount of the drive that is not reported to the operating organization, and not accessible to the user. This allows room for the bulldoze to motility and delete items without affecting the overall storage chapters.


SSDs are newer technology, and as such, are more expensive than HDDs. Although they are catching up, information technology tin be harder to find large-capacity solid country drives. HDDs tin can exist every bit much equally 2.5 times larger.

Benefits of an SSD

Why choose a solid state drive? SSDs evangelize faster load times for games, applications, and movies. Because of the technology they employ, SSDs are lighter and better able to withstand move and droppage. In addition, solid land drives use less energy, allowing computers to run cooler.

One of the biggest benefits of an SSD is how much faster they are than HDDs. For example, the Crucial P5
is our fastest NVMe SSD, delivering impressive read/write speeds up to 3400/3000MB/s. Even portable SSDs are faster than HDDs. With read speeds upwards to 1050MB/due south


and capacities up to 2TB, the
is up to 100x faster than USB flash drives


and upwards to seven.5x faster than traditional hard drives


Compare Crucial solid state drives.

Is an SSD a hard drive?

Put simply, an SSD isn’t the same equally a hard bulldoze. Hard drives use magnetically sensitive platters which are moved past a motor, whereas an SSD uses flash memory without whatsoever moving parts, meaning they are faster.

The decision

The difference between hard drives and solid state drives is in the technology used to store and retrieve data. The table beneath illustrates some of the differences.

HDDs are cheaper and you can become more storage space. SSDs, nevertheless, are incredibly faster, lighter, more durable, and they use less energy. Your needs will dictate which storage drive will work best for you lot.

Observe out about the benefits of solid land drives.

Cost Speed Durability Highest capacity Energy efficiency
HDD Cheaper Slower Less durable x TB Utilise more than energy
SSD More than expensive Faster More durable 4 TB Apply less energy

  1. Sequential read speed of 1050MB/s specific to Crucial’southward portable X8 drive.
  2. MB/s speed measured as maximum sequential performance of device as measured by Crucial on a loftier-operation desktop computer with Crystal Disk Mark (version 6.0.2 for x64). Your performance may vary. Comparative speed claims measured as maximum sequential operation of similarly situated portable SSDs, mainstream portable HDDs and mainstream USB flash drives from vertically-integrated manufacturers selling under their own brands as of June 2019.

Source: https://www.crucial.com/articles/about-ssd/ssd-vs-hdd