Anatomy of SSD. How it is built and how it works so hard? – Virtual Poland

 
  Popular among gamers and enthusiasts, SSDs, more and more often also for ordinary computer users. How is it different from conventional hard drives?

 
 SSD stands for Solid State Drive. In Poland it adopted the term solid-state drive, due to the lack of mechanical components and the structure rests on NAND flash memories. For comparison, traditional HDD (Hard Disk Drive), data storage use rotating magnetic platters.

 
  SSD vs. HDD

 
 Modern HDDs are packed with electronics, but still conceal the driving engine of the servo control plates and heads. In the case of SSD replacement shock sensitive plates for flash memory it makes them lighter and more resistant to damage and overload. In the case of a typical SSD can find a printed circuit board (PCB) to which all components are soldered.

 
 
 Its structure SSD at first glance can be associated with popular USB flash media (memory stick). Of course this is a simplification, because solid-state drives structures are very advanced. They used NAND flash memory is characterized by high efficiency and long service life. Their work is controlled controller, acting as the “brain”. Finally, the SSD communicates with the motherboard through an efficient and fast interface.

 
 
  Memory NAND flash

 
 They are the heart of SSD and are used to store data. They were developed in the early 80s, but the story of their success on the market is closed in the last decade. Earlier, the memory was too expensive and offered too little capacity to become a popular medium.

 
 The solid state memory are grouped into modules (bone) and placed on the PCB. The miniaturization of circuits has led to the fact that today a typical drive offers a storage capacity of 120 GB to 1 TB. In a few years we can expect dorównujących capacities of SSD HDD drives. Currently, because of the price, the most popular are drives 120-128 GB and GB 240-256.

 
 
 In a market ruled by art MLC (Multi Level Cell). Memory based on this solution have the best ratio of performance to the viability and affordability. A single MLC memory cell can store two bits of data.

 
 
 On the market you can also find professional discs with memories of SLC (Single Level Cell), where a single cell is a carrier for a 1 bit of data. They are characterized by very high reliability, but also the high price. A relatively new solution is the memory TLC (Triple Level Cell) – high-density storage of data, 3 bits in the cell. They are cheap, but their life span is several times shorter than the life cycle of MLC memory.

 
 
  Controller
 

 
 The system controls the operation of the drive is the key to its performance. It performs all tasks related to writing, reading and queuing data. Reliability controller is the case with SSD drives extremely important. The controller determines at least about which memory cell data is stored. This allows you to extend the life of the drive, and thus ensures the trouble-free operation for many years.

 
 
 One company known for its high quality is Marvell controllers. It uses them quite extensively Plextor. In the segment of budget solutions we will also find brands such as Silicon Motion and Phison. Some manufacturers of SSDs, even Intel, also use their own controllers.

 
 With the controller work very closely related is the question of the cache (cache) – additional DRAM module, located on the PCB. It plays the role of a tray, a kind of pocket that facilitates controller queuing. The general opinion, the cache is larger, the better. It is not a rule. More cache usually find in a larger capacity drives that offer higher-speed data writing. On the other hand, the SSD based on popular SandForce controllers have no cache at all.

 
 
  Interface

 
 Like the HDD, SSD drive manufacturers prefer to reach for the most popular solution on the market – SATA 6 Gb / s. This is beneficial for users as it enables replacement of the hard disk to the semiconductor does not require greater computer knowledge.

 The same interface does not change the fact that the difference in performance between the HDD and the SSD is usually huge. HDD models achieve the most efficient transfers at the level of 150-200 MB / s. SSDs often 450-500 MB / s, and the more expensive models can come close to the limits of capacity SATA 6 Gb / s (approx. 570 MB / s). To work around the phenomenon of “bottleneck” SATA, manufacturers turn to alternative solutions. Hence ultra-efficient SSDs using the PCI Express interface.

 
 
  What else should I know about SSDs?

 
 SSD manufacturers like if their products stand out from the competition. Hence the attention to appearance, bright colors and fun stickers. From a user perspective is more important than appearance but robust aluminum housing.

 
 SSD is not divided into 2.5 and 3.5 inch HDDs like. Standard is a universal format 2.5-inch drives SATA 6 Gb / s and the thickness of 7 mm housing. As a result, SSDs can also put the ultrabooks.

 
 Additional software is a nice touch from the manufacturer. Choosing the SSD, you take a look at what we get in gratisie. A popular addition there are programs for data migration or clone the disk, such as NCI Echo 3. Equally it may be useful optimization software disk. For example, the Samsung SSD Magician offers application and Plextor rich software package: PlexTurbo 3.0 PlexCompressor and PlexVault.