SSD (Solid-state drives – Solid State Drives) have a significant performance advantage over traditional mechanical hard drives. SSDs are available for PCI-Express interface, also known as PCIe, as well as for the SATA (Serial Advanced Technology Attachment – Serial Attached Advanced Technology), which is used for traditional hard drives.
Instead of magnetic disks used to store data on hard drives, solid state drives use flash memory, a type of semiconductor memory that retains its data when you turn off the power. Flash memory has no moving parts and is significantly faster than a hard drive, especially for reading files that are already on the drive. Traditional hard drives have a lower cost per byte and greater storage density than solid state drives, although many users consider the performance benefits of SSD are sufficient to justify the high cost they have.
The units PCIe solid state type are presented in the form of a plate that slides into a PCIe connector. A related form, mini PCIe, has a smaller size that fits the narrowest inside laptops. SSDs are also presented in standard housings of 1.8 inches (4.5 cm), 2.5 inches (6.3 cm) and 3.5 inches (8.8 cm), which conform to the bays standard desktop computers and laptops. A PCIe SSD has the advantage of not occupy a standard drive bay, which gives you the flexibility to mix and match different types of units, solid traditional state in your computer. In addition, you can purchase an SSD drive standard form factor of knowing that will fit virtually any computer; legacy systems, especially, you may not have a PCIe slot.
The SATA III interface is capable of transferring data at a rate of 6 gigabits per second, enough for most users and commercial applications, especially when traditional hard disk drives are used. However, SSDs are able to achieve higher transfer rates, which in some instances; SATA limits the performance of the SSD. The PCIe interface has data transfer rates ranging from 1-2 gigabytes per second, about two to four times the speed of the SATA interface.
At the time of publication, the capabilities of SSDs ranging from 30 GB to 960 GB; most manufacturers offer capabilities for SATA drives or PCIe formats. The smaller form factor of the mini PCIe interface these SSDs currently limited below 100 GB. Flash chip technology is improving year by year, so as the storage density flash chips is increased, will increase the capacity of SSDs of all sizes and shapes.