SSD vs HDD: Full Comparison of Storage Drive

ssd vs hdd

In this article, we’re going to compare SSD vs HDD, which are commonly used to store the data permanently in desktop and the laptops. Now, conventionally these hard disk drives are used as a storage solution in desktop and the laptop. These hard disks drive are in use for more than two decades. But in recent years, the SSDs are gaining the popularity because of its speed and the performance.

So, in this article, let’s compare these two drives in aspects like

  1. Speed and Performance
  2. Internal Structure and Working Principal
  3. Form Factor
  4. System Interface
  5. Storage Capacity and Cost
  6. Power Consumption and Reliability
  7. Data Durability

Comparison of SSD vs HDD Storage Device

1. Speed and Performance

ssd vs hdd

The technology of hard disk drive has improved significantly over the past two decades. And the data density of this drive has increased tremendously. But the speed of the hard disk drive hasn’t increased at the same pace. Typically, the access time of today’s hard drive in the range of few ms(millisecond). And the sequential read and write speed is typically around 100 Mbps. If you are thinking the speed of the hard drive is not bad then let me tell you that the access time of the RAM and the cache memory which is used in the computer is in the range of nanoseconds. Which is significantly less than the access time of these hard drives.

So, even if you have very high-end CPU, coupled with graphics card and RAM, still you will not be able to extract the best performance out of the system if you are stuck with the slow hard disk drives. The top CPU and GPUs, the performance of the system will definitely increase. But because of the limitation of the hard drive, the system boot time and the opening of the applications will not be that fast.

While on other ends, if we talk about the SSDs, they are much faster and have access time typically in the range of microseconds. And the typical sequential read and write speed is in the range of 400 to 500 Mbps. And in fact, even if it is possible to achieve the sequential read and write speed in the range of Giga Bytes per second using this SSDs.

2. Internal Structure and Working Principal

ssd vs hdd

Now let’s look into the internal structure of these drives and their internal structure of these drives and let’s find out why SSDs are so fast and HDDs are relatively slow as compared to SSDs.

So, if you look inside the HDDs, it consists of rotating disk, which is commonly known as the platers. These platters rotate at the typical speed of 5400 or 7200 RPM in laptops and it can go up to 10,000 RPM in desktop computers. In some enterprise HDDs, the speed can go up to 15,000 RPM.

So, in these HDDs, the data is stored magnetically on these platters using the head. And typically the data is stored in this hard disk drive in form of tracks and the sectors. Now as it involves the mechanically moving parts, there is a limitation on the speed at which the data can be accessed or written on these hard disk drives.

ssd vs hdd

On the other end, the SSDs are designed using the flash memory. And to be precise if I say, they are designed using the NAND flash memory. So, as these SSDs are designed using the NAND flash memory and don’t have any moving part, they have very fast access time and very low latencies.

So, apart from the flash memory, the SSD also contains the microcontroller and the small cache memory. Using the microcontroller, the flash memory cells can be accessed or programmed. And using the cache memory it is possible to store the incoming and the outgoing data temporarily.

3. Form Factor

ssd vs hdd

 

Today’s HHDs are typically available in two form factors. For desktop, it is available in 3.5-inch form factors, while for a laptop it is available in 2.5-inch form factor. On the other end, the SSDs are available in many form factors. The most common is the 2.5-inch form factor, where these drives can be used or replaced in place of HDDs. Apart from these, the mSATA and the M.2 SSDs are available in very small form factors and they are used in ultrabooks and tablets.

4. System Interface

ssd vs hdd

 

In the comparison of SSD vs HDD, the system interface defines how these drives are connected or interfaced with the systems. So, the earlier hard drives were connected to the system using the PATA interface which is known as the parallel ATA. But today’s hard drives are connected to the system using the SATA interface. While enterprise hard drives are connected to the system using the SAS protocol. On the other end, if we talk about the SSD, mSATA, and SATA hard drives are connected to the system to the system using SATA interface. While M.2 SSD can communicate with the system using either SATA or PCI express bus.

 

5. Storage Capacity and Cost

Now if we compare SSD vs HDD in terms of the storage capacity then for the HDDs, 1TB capacity is most common in desktop and laptops. But for desktop, even 10 TB of the hard drives are commonly available in markets. And if we talk about the SSDs, then as of now the SSDs are available from 120 GB up to 4TB. For laptops typically, it is available from 120 GB up to 1TB. While for the desktop it is available up to 4TB.

Now, if we talk about the cost, then these SSDs are much costlier than the HDDs. As of now the cost per GB for SSD is almost 3 to 4 times the HDD cost. But as the demand for SSD is growing, the cost is also reducing. And perhaps one day, it will become as cheap as the today’s hard disk drives.

6. Power Consumption and Reliability

ssd vs hdd

HDDs involve the mechanical moving part of the power consumption of this drive is more than the SSDs. They are more prone to the damages in case of shock and the vibrations.

7. Data Durability 

ssd vs hdd

In terms of the data durability, hard drives are more durable and data can be stored for longer times without being powered up. Apart from that as we have seen SSDs are designed using the flash memory and because of that, the number of programs is erased cycles that can be performed on these SSDs are limited. Typically, it used to be in the range of 10000 to 100000. It depends upon the quality of the controller as well as the internal structure of the flash memory.

ssd vs hdd

Some manufacturers also provide the endurance rating for these SSDs and typically it is defined by the term drive writes per day. It means that the number of times the user capacity of the drive can be written per day over the warranty period. For example, if you have 100GB of a drive, which has DWPD rating of 10, it means that 1000GB or 1TB of data can be written into this drive every day over the warranty period. So, basically, this term defines the endurance rating for the SSDs. But for the most of the users, this rating is quite significant. And even if someone uses this SSD quite extensively then also it will work reliably over more than 5 years.

Also, read: What is ZIP and RAR file? How does it work?

Conclusion 

So, overall SSDs have many advantages over the HDDs. But as of now, these SSDs are quite costlier than the hard disk drives. So if someone is looking for big storage pull, with the reasonable cost then he can go for the HDDs. While on the other end, if someone wants very fast performance and willing to pay extra money for that performance then one can go for the SSDs. Now, I hope that this SSD vs HDD comparison article has been well understood by you.