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About hard drives
Hard disks and SSDs are the memory of a computer among the PC components. However, the way they work differs. Read our guide to find out what the differences between hard drives and SSDs are, what the benefits of flash drives are, and what to look for when you buy them.
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Where are hard drives and SSDs used?
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What are the advantages and disadvantages of an SSD compared to a hard disk?
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SSD hard drive shelf life?
- Current interfaces for SSDs and hard drives
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What should ich be aware of when buying a hard drive or SSD?
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Our practical tip: Not every hard disk is suitable for operation in NAS!
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FAQ – Frequently Asked Questions about Hard Drives and SSDs
Where are hard drives and SSDs used?
No computer can run without a hard drive, whether it's a desktop computer, a notebook, or a server in the data center. More and more, the classic SATA HDD is being replaced by so-called solid state drives (SSD). An SSD hard drive is based on flash memory. This is also used in mobile devices such as tablets, smartphones or mp3 players. In short, where data, images or music are stored permanently, either an HDD or a solid state drive is used. In our assortment you will find a large selection of internal hard disks and external hard disks. In addition, we offer a wide range of hard disk accessories such as mounting frames or hard disk enclosures.
What are the advantages and disadvantages of an SSD compared to a hard disk?
While a conventional SATA HDD stores the data on fast-rotating magnetic disks, SSD hard disks are based on flash memory chips. The biggest advantage of SSD hard drives is the significantly higher speed of data transfer, which can be over 4000 MB/s depending on the interface. Even the fastest HDDs, on the other hand, achieve values of 300 MB/s. In addition, SSD hard drives are very robust. There are no moving parts inside, use is not a problem even when driving bumpy. In an HDD, the read/write heads would hit the rotating magnetic disks and leave defective sectors.
Minimal access times, low power consumption and absolutely silent operation can also be seen as a plus point for the SSD hard drive. So far, everything seems to speak for SSD storage, but there are definitely disadvantages:
SATA HDDs are currently available with a storage capacity of up to 18 TB. On the other hand, the maximum storage capacity for a solid state drive is currently 8 TB.
In addition, an appropriately dimensioned SSD hard disk is considerably more expensive than an HDD hard disk.
Durability of SSD hard drives
The media are constantly discussing how durable an SSD hard drive is. The question is perfectly justified, since flash memory blocks can only handle a certain number of write cycles. The number of cycles that are accurate depends primarily on the type of memory in the drive. Four different flash memory variants can currently be enumerate here: SLC stands for single-level cell and means that each cell can store exactly 1 bit. SLC storage is the most durable, but also by far the most expensive. Such SSD hard disks are therefore used wherever a high write load occurs. This can be the case for a server or a workstation, for example. The abbreviation MLC means Multi Level Cell. Typically, this type of memory stores 2 bits per cell. MLC storage has become a solid standard for internal SSD drives. It offers a high durability in combination with a good price-performance ratio. MLC-based SSD hard drives are suitable for gaming machines, but also for professional applications, where a high write load is not permanently required.
A TLC memory (Triple Level Cell) stores 3 bits per cell. The available write cycles decrease significantly compared to the MLC memory. However, TLC is much cheaper. An SSD hard drive of this type is suitable for computers and notebooks in the consumer area and for simple office computers. QLC (Quadruple Level Cell) is the latest development in flash memory. 4 bits can be stored per cell. This significantly reduces the price, but the number of write cycles available is lower. In terms of speed, there are also drawbacks to the other memory types. Such an internal SSD is therefore only suitable for consumer computers or office computers on which simple tasks are performed.
But what was the meaning of these values in practice? Each manufacturer guarantees different TBW values (TBW = Total Bytes to be written) for its products. This is the number of data that can be written to an SSD during its lifetime. While a 1000 gigabyte SSD with SLC storage can have a TBW of 17.5 petabytes (PB), the TBW number is only 9 PB with an SSD of the same size with MLC storage. With TLC, the value drops to 2.5 to 5 PB and only reaches 360 TB with QLC.
Current interfaces for SSDs and hard drives
Internal HDDs are usually always connected via a SATA interface. This applies to both 3.5-inch hard drives and 2.5-inch hard drives. On the other hand, in workstations or servers, SAS hard disks are mostly used, which have largely replaced the older SCSI standard. Internal SSDs are also available with SATA interface. Such models are usually available in 2.5-inch format. GB SSDs are also available in 1.8- or 3.5-inch housings.
A very interesting alternative is M.2-SSDs: These compact plug-in cards are plugged directly into the corresponding slot on the motherboard without cables. But beware, M.2 is not the same as M.2! The interface can be connected via SATA as well as via PCIe. The differences are considerable: While a M.2 GB SSD achieves a typical read speed of up to 550 MB/s, the PCIe version has more than 3000 MB/s. A PCIe 4.0 SSD achieves even higher transfer rates at a compatible slot. External hard disks usually have a USB interface. If possible, avoid USB 2.0 and at least access a model with USB 3.0 or better still USB 3.1. This is especially true for external SSD hard drives. USB 2.0 would only slow down the drive.
What should ich be aware of when buying a hard drive or SSD?
An internal SSD drive should be part of any modern desktop PC. The high speed of the data transmission enables a particularly responsive system. Annoying waiting times until the next program is loaded are largely eliminated. A good compromise is a smaller flash drive in combination with a hard drive that has enough GB of memory. The operating system and frequently used programs are ideally located on the fast SSD, while data and less frequently used tools are stored on the internal SATA-HDD.
Only SSDs should be used in a notebook due to their robustness. For older notebooks, you can connect a 2.5-inch model via SATA; for newer devices, a particularly fast M.2-SSD is recommended. For simple office activities, a capacity of 250 GB is usually sufficient. The use of SSDs can also make sense when operating a NAS system. Flash drives require less power and do not need to be cooled, at least in the case of 2.5-inch SATA models. However, if you need a storage capacity of several thousand GB, there is no way to go past HDD drives.
Our practical tip: Not every hard disk is suitable for operation in NAS!
A NAS usually runs 24 hours a day and 7 days a week. A normal desktop hard drive is not designed for such a load. Therefore, make sure that the hard disk is suitable for continuous operation when you buy it. Many manufacturers have hard disks in the program, which are specially optimized for use in NAS systems.
FAQ – Frequently Asked Questions about Hard Drives and SSDs
What was an SSHD hard
An SSHD is a hybrid drive that combines flash memory with a conventional HDD. Here, first write to the "turbo memory" and then from the solid state memory to the hard disk. This has the advantage that the user receives a system with a similar reaction speed as with a SATA-SSD. If the flash memory, which is usually scarce, is not cleared quickly enough, the transfer rates quickly fall to the level of the multiple GB hard disk.
What was a RAID system?
RAID stands for Redundant Array of Independant Disks. This feature is provided by dedicated controllers and allows you to organize multiple HDD or SSD drives. For example, at RAID level 0, each file to be saved is stored equally on several hard disks. There is no redundancy in this case, but the transfer rates are increasing. With RAID 1, one file is stored on several hard disks and thus a redundancy is generated.