A new and exciting addition to computer storage technology is the SSD or Solid State Drive. Tech enthusiasts have welcomed this as a significant improvement over the HDD or Hard Disk Drive.
But why are SSDs considered superior to HDDs?
Let us answer some important questions about the differences between SSDs and HDDs. We will also discuss the advantages that SSDs provide over HDDs.
What is an HDD?
Hard Disk Drives or HDDs have been in the market for over 50 years now. These are reliable storage devices that use moving magnetic parts to store data on your computer. An HDD contains multiple spinning disks inside which data is stored magnetically.
Speaking of the design, an HDD has an actuator arm with multiple transducers called “heads”. These heads can read and write data on the disk.
The process might seem similar to that of the record player. You can compare the arm with transducers to the needle on the record player. It moves across the surface of the disk so that the heads can access and display different data at different locations on the disk. HDDs also contain an I/O controller and firmware that instructs the hardware. It controls the disk space and communicates data with the rest of the system.
HDDs are considered a legacy technology. Manufacturers have tested and developed HDDs for a long time by introducing frequent updates to memory sizes, rotation speeds, and firmware.
HDDs are usually available in two formats:
- 5 inch (ca. 64 mm) disks – you would find these in laptops.
- 5 inch (ca. 89 mm) disks – used in larger devices such as desktop computers.
The plates or disks in an HDD spin at preset speeds somewhere between 4200 rpm and 7200 rpm (specifically for consumer PCs).
These speeds relate to the read/write capacities of the HDD. The higher the preset rotation speed, the faster a hard drive will be able to read and write data.
When you instruct your computer to retrieve or update data in an HDD, the I/O controller locates the data and passes the information to the actuator arm. The arm takes the transducers (“heads”) to the location where that data is located. Then, the read/write head gathers the data by reading the presence or absence of a charge in each address. If you provide instructions to update the data at a specific location, the read/write head changes the charge on the instructed sector.
What is an SSD?
SSDs (Solid State Drives) are so named because they do not have any moving parts.
An SSD stores data in integrated circuits that constitute a single circuit board. Solid state drives essentially use flash memory to store, read and write data.
There are a number of minute moving parts inside conventional HDDs. However, all that complication is absent in an SSD. This makes SSDs more effective, compact and customizable compared to HDDs.
You can consider SSDs as very large USB drives – much like pen drives. The basic operating technology is the same in both cases. Solid State Drives use the NAND (NOT-AND) logic gate. It is the same logic gate as in flash memory drives. Transistors read and record positive or negative charges to store and update data. The gates are arranged in a grid pattern. These grids are further organized into blocks of various sizes. Each individual row that makes up a grid is called a page.
An SSD controller performs important functions such as reading and accessing data and tracking data locations. When you instruct your computer to retrieve or change data, the SSD controller looks up the page and block the address of the requested data. It then reads the charge status and displays the recorded information. When you update the existing data on an SSD, the controller essentially updates all the data in the particular block. The controller copies the existing data on the previously allocated block to an alternative block. The empty block is then erased and the controller allocates a new block to rewrite the changed data on it.
It is important to note that the number of times any block can be rewritten is finite. Some very important data maintenance processes run in the background to prevent premature wear or data loss in an SSD. These are as follows:
- TRIM – a code that instructs the SSD controller to skip rewriting some data while erasing blocks.
- Garbage Collection – a process that ensures the information in the old block is completely erased and that the block is available to be written to again.
- There is also a separate algorithm that distributes an equal number of read/write processes to individual blocks in the SSD. This process is called Wear Leveling. It is conducted automatically in the background while the drive is working.
Why are SSDs more expensive than HDDs?
It is true that you would have to shell out extra money for SSDs. However, the higher cost can be justified by the reasons below:
- SSD’s use NAND Flash technology, which follows a separate and higher pricing scheme compared to the DRAM (Dynamic Random Access Memory) technology used in system memory (such as HDDs).
- Typically, the components of SSDs show higher performance output and durability. These components are sold at higher prices than the components used in conventional USB drives. This increases the production cost for manufacturers and leads to a higher selling price.
- Also, it takes many hours of compatibility and stability testing to ensure that the SSD controller and related firmware work seamlessly. These steps add to the cost of producing SSDs.
- The demand-and-supply relationship in the SSD market is much more dynamic as compared to the more stable market of HDDs. Large suppliers of components who are also capable of producing SSDs themselves and selling them at lower costs do not do so. Instead, they sell the components to smaller manufacturers who have to pay a higher cost to produce the SSDs. This increases the demand for both the components and the final product, creating a gap that translates to higher prices in the market,
The above reasons entail that SSDs cost more per unit of storage than HDDs. But this price gap has shortened swiftly with each passing year. For example, a 128 GB SSD that was sold between $200 and $250 in 2010-2011 now sells for $20 to $25 in 2022.
Benefits of SSD in a Computer
Some very significant benefits of using SSDs over HDDs are as below:
- SSDs have no moving parts. It makes them more durable as the wear and tear are minimal in comparison to the wear you would observe on an HDD.
- As SSDs lack a spinning disk, their dimensions can be very small. M2 SSD drives are the size of a stick of chewing gum! This makes them a suitable choice for small, compact devices such as Chromebooks, thin-and-light laptops or 2-in-1 convertible laptops.
- In HDDs, there is a delay between when the system starts up and when it reaches optimum rotation speed. It is termed “latency” in HDDs and can sometimes be too frustrating to deal with. Unlike HDDs, there is no need to wait for SSDs to reach a specific rotation speed to start working. This reduces the data access time drastically, which is a boon for users.
- SSDs are usually allocated an extra provision of storage space apart from the visible space. A fixed amount of the drive space is inaccessible to the system and the user for data storage. This allows the drive controller and firmware to work smoothly. The SSD controller can move and delete items in this buffer space without compromising the overall storage capacity of the drive. HDDs do not have a buffer space on the disk. The background algorithms use the disk space to function. This results in further latency.
- HDDs present a significant danger of data loss due to the moving magnetic parts. These components are susceptible to physical damage sooner than the components in an SSD. Having shunned moving parts completely, SSDs effectively diminish the prospect of data loss.
- SSDs have a cooler running temperature than HDDs, and use a lesser amount of energy. This prevents overheating of the system and increases the lifespan of your device.
How do I know if I can upgrade or if I already have an SSD?
If your device comes with a preinstalled SSD, it will be mentioned in the device features listed in the manual. However, if you are a techie and understand computer hardware and software thoroughly, you can check out the BIOS settings of your device.
It will provide you with information regarding the type and quantity of storage space on your device. However, not many users are aware of the specific settings that need to be accessed or changed in the BIOS.
We understand that this can be too frustrating, especially for casual users. If you are looking to speed up your computer with our upgrading an SSD, read our Do It Yourself PC Tune-up Guide.
We at Gophermods are ready to assist you with upgrading your device as per your requirement and at affordable prices. Simply head over to our computer repair page for a quote.