Difference Between SSD and HDD

There is no comparison between SSD (Solid State Drive) and HDD (Hard Disk Drive). SSD has outstanding performance with 20,000 times faster random data reads compare to HDD. HDD is an electro-mechanical legacy storage device that uses spinning disks to store data magnetically, whereas SSD has no moving parts and stores data in a NAND chip. NAND technology used in SSD doesn’t need the power to retain data.

Inside HDDs, disks/platters are spinning at a high RPM (7200RPM*), and read/write heads move back and forth to read or write the data magnetically. SSDs are just electronic circuit boards. SSD is faster, reliable, more power-efficient, small in size (form factor), makes less noise when operating (silent operation), and more.

Reliability of SSD and HDD

Hard disk drives consist of many moving parts like an actuator, disk/platter, spindle, and a read/write head that lead to mechanical failures. Shock and vibration have a role in the HDD mechanical failure. If you drop a hard disk drive (HDD), chances are it will fail and stop working. Many HDDs have a built-in shock sensor. There is no warranty if the disk drive experiences a shock that is over its threshold limit. Along with shock and vibration, hot and cold conditions also contribute to hard disk failures.
HDD stores data in a circular disk or platter. Platters are spinning at a constant speed. So, reading data from the outer edge is faster than the center. While reading from the outer edge, the head can read more data because there is a larger area available per revolution. To compare with, SSD (Solid State Drive) is just a chip (electronic circuit). No moving parts and no mechanical failure.

Fragmentation Factor in SSD and HDD

Fragmentation is another performance loss factor in the case of hard disk drives. HDD stores data in the first available empty location. Because files are constantly being written, deleted, updated, and resized, a file may be stored in many different locations over different platters. Fragmentation makes your hard disk do extra work that can slow down your computer.
You can use defragmentation software to defrag and speed up the HDD. Disk Defragmentation might take from few minutes to a few hours to finish. (1)
SSDs (Solid State Drives) have very high random data reads. So are not impacted by fragmentation. In random reads, SSDs can be more than 20,000 percent faster than high-performance HDDs. (2)

When to choose HDD (Hard Disk Drive)

Go for an HDD if a large amount of data is being stored in terabytes (TB), and it is not accessed often. Examples include pictures, movies, and scanned documents/books, etc. It is the only scenario where traditional hard disk drives are better and less expensive. As of today, August 25, 2021, the price of SSD is higher than the HDD. Check and compare the price before ordering the hard disk drive (HDD).

When to choose SSD (Solid State Drive)?

1. Entry-level low-priced SSDs are faster than traditional HDDs. SSD can give a new life to an aging PC. Newer laptops or desktops get instant performance boosts with SSD instead of HDD.
2. To replace the Boot/Startup drive, most manufacturers offer cloning software to replace HDD with SSD.
3. SSDs are faster than hard disk drives.
4. The durability and reliability of an SSD are better than HDD.
5. SSDs are power and energy-efficient
6. SSD has Less weight and no noise
7. available in more practical sizes/form factors

Summary

Solid State Drives have many advantages over hard disk drives. As their capacities increase while costs less, the future belongs to SSDs.

1. Better Performance: SSDs are faster than HDDs. SSDs are 20,000 times faster than HDDs in random data reads.
2. Durability: Shock handling of SSD is better than HDD.
   1. SSDs can withstand shock and vibration better than HDDs
   2. SSDs remain operational in harsh environmental conditions like heat and cold.
   3. SSD has no moving parts, so no vibration or virtually no heat output, which improves life span.
   4. SSDs have five years warranty.
3. SSDs consume less power and generate less heat than HDD.
4. Storage Capacities: SSDs are available in 120GB to 30.72TB capacities, whereas HDDs can go anywhere from 250GB to 20TB. (3)
5. SSD is just an electronic circuit board and has less weight and no noise while in use.
6. More practical sizes/form factors
   1. HDDs are commonly available in 2.5 inch and 3.5-inch form-factor
   2. For SSD, 2.5-inch is a common form factor for desktops and laptops as a replacement for HDD.
   3. mSATA is a bare circuit board if space is an issue
   4. M.2 is also a bare circuit board for both SATA and PCIe NVMe.