Comparison between Conventional hard drives (HDD), Solid state drives (SSD), and Solid State hybrid drives (SSHD).


Conventional HDD

Solid State Drives (SSD)

Hybrid hard drives (SSHD)

Technology HDDs are conventional type of drives which contains a platter where in your data is stored, and a head which reads and writes your data on the platter SSDs are the latest technology as of now, which is based on chip based memory (NAND flash) where in your data is stored. No mechanical parts present. Just like a pen drive. Mixture of SSD and HDD, where in your data is stored in conventional HDD, but the SSD part is used to make the data access faster.
Read / Write Speed (average) Read – 128 MB/Sec

Write – 120 MB/Sec

Read – 550 MB/Sec

Write – 520 MB/Sec

Read – 175 MB/Sec

Write – 162 MB/Sec

Rotation Speed (RPM) 5400 Rpm

7200 Rpm

N.A. as no mechanical parts present (chip based) 7200 Rpm
Access time 5.5-8.0 ms 0.1ms
Random I/O performance Highest 400 io / sec Upto 6000 io /sec
Speed noticeable to user Slow in comparison to SSD and SSHD Highest Speed Medium or Medium high speed. Although the data is stored in convectional HDD but while working the frequently used data is stored in SSD section for faster access.
Data Durability Data stored in HDD will degrade slower Data stored in SSD will degrade faster
Reliability Failure rate 2-5% Failure rate 0.5%
Power utilisation Consumes between 6 – 15 watts Consumes between 2-5 watts
Pricing in comparison to space Low High / Very high Medium
Which is better Good for data storage Good for loading operating system and games Good for data storage and can also be used for loading operating system
Where to use Use it for data storage Use it for loading operating system and games and video compilation Use it for data storage
How use if you are using only one drive in your system Load both operating system and data into a single drive Primarily use it for loading operating system, keep a small area where in your working data can be stored and than important data can be shifted to external HDD Load both operating system and data into a single drive
Data recovery options If the HDD is failing or has crashed there are more chances of data recovery available as generally the logic card is damaged. If the platter or head is failing in that case there are chances of data recovery if not full partial is possible No option is available as nothing is mechanical and it is higher version of pen drives May be possible. Do not had such experiences yet.

System management tip – Looking at the cost and reliability of HDD / SSD and SSHD, it is preferable that you load the operating system in SSD and store data in your HDD or SSHD. This will not only improve the performance of your system but also preserve your data efficiently.

No matter what ever you do or which drive you select, always keep a backup of your important data, and for that purpose using CD’s, DVD’s, or Blue Ray Discs are more reliable than HDD, SSD or SSHD.

Note : The informations are based on personal experience and few details are taken from internet.

Author : Debashish Ray, Jalpaiguri, Bharat