2 Expansion Cards, Storage Devices, and Power Supplies Flashcards
What is a Network Interface (NIC) Card ?
An expansion card that connects a computer to a network so that it can communicate with other computers on that network. These usually come integrated on the motherboard.
input/output card
any expansion card that enhances the system, allowing it to interface with devices that offer input to the system, output from the system, or both. The following are common examples of modern I/O cards:
USB cards
Storage cards, such as eSATA
Thunderbolt cards
Hard Disk Drive Systems
Controller
This component controls the drive. The controller chip controls how the drive operates and how the data is encoded onto the platters. It controls how the data sends signals to the various motors in the drive and receives signals from the sensors inside the drive.
Hard Disk
This is the physical storage medium. Hard disk drive systems store information on small discs also called platters, stacked together and placed in an enclosure.
Host Bus Adapter
The host bus adapter (HBA) is the translator, converting signals from the controller to signals that the computer can understand.
Anatomy of a Hard Drive
Platters
Read/write heads
Tracks
Sectors
Cylinders
Clusters (allocation units)
clusters / allocation units
Filesystems laid down on the tracks and their sectors routinely group a configurable number of sectors into equal or larger sets called clusters or allocation units.
Spin rates for platters in conventional magnetic hard disk drives:
5,400 rpm
7,200 rpm
10,000 rpm
12,000 rpm
15,000 rpm (SAS drives)
Advantages / Disadvantages of SSDs
Advantages of SSDs:
* Faster start-up and read times
* Less power consumption and heat produced
* Silent operation
* Generally more reliable because of a lack of moving parts
* Less susceptible to damage from physical shock and heat production
* Higher data density per square centimeter
Disadvantages of SSDs:
* The technology to build an SSD is more expensive per byte.
* All solid-state memory is limited to a finite number of write (including erase) operations.
* Lack of longevity could be an issue. As the technology matures, this is becoming less and less of a problem.
Hybrid Drives
A cost-saving alternative to a standard SSD that can still provide a significant increase in performance over conventional HDDs is the hybrid drive. Hybrid drives can be implemented in two ways:
- a solid-state hybrid drive
- a dual-drive storage solution
Solid-State Hybrid Drive
The solid-state hybrid drive (SSHD) is a conventional HDD manufactured with a substantial amount of flash memory–like solid-state storage aboard. The SSHD is known to the operating system as a single drive, and individual access to the separate components is unavailable to the user.
Dual-Drive Solutions
Dual-drive storage solutions can also benefit from technologies such as Intel’s Smart Response Technology (SRT). However, because they are implemented as two separate drives (one conventional HDD and one SSD), each with its own separate file system and drive letter, the user can also manually choose the data to move to the SSD for faster read access. Users can choose to implement dual-drive systems with SSDs of the same size as the HDD, resulting in a fuller caching scenario.
3 SSD Communication Interfaces
SATA, PCIe, and NVMe
PCIe standards and transfer rates
ver. t rate tp/lane total x16
v1.0 2.5 GTps 250 MBps 8 GBps
v2.0 5.0 GTps 500 MBps 16 GBps
v3.0 8.0 GTps 1 GBps 32 GBps
v4.0 16.0 GTps 2 GBps 64 GBps
v5.0 32.0 GTps 4 GBps 128 GBps
NVMe
Non-Volatile Memory Express (NVMe) is an open standard designed to optimize the speed of data transfers. NVMe drives are frighteningly fast. Current NVMe SSDs can support data reads of up to 3.5 GBps
SSD Form Factors
mSATA (mini-Serial ATA) and M.2 (M dot 2)
M.2 Key Characteristics
A / PCIe x2, USB 2.0 / Wi-Fi, Bluetooth, and cellular cards
B / PCIe x2, SATA, USB 2.0, USB 3.0, audio / SATA and PCIe x2 SSDs
E / PCIe x2, USB 2.0 / Wi-Fi, Bluetooth, and cellular cards
M / PCIe x4, SATA / PCIe x4 SSDs
RAID
Redundant Array of Independent (or Inexpensive) Disks (RAID). Multiple hard drives can work together as one system, often providing increased performance (faster disk reads and writes) or fault tolerance (protection against one disk failing). RAID can be implemented in software, such as through the operating system, or in hardware, such as through the motherboard BIOS or a RAID hardware enclosure. Hardware RAID is more efficient and offers higher performance but at an increased cost.
RAID 0
RAID 0 is also known as disk striping, where a striped set of equal space from at least two drives creates a larger volume. This is in contrast to unequal space on multiple disks being used to create a simple volume set, which is not RAID 0. RAID 0 doesn’t provide the fault tolerance implied by the redundant component of the name. Data is written across multiple drives, so one drive can be reading or writing while another drive’s read-write head is moving. This makes for faster data access. If any one of the drives fails, however, all content is lost.
RAID 1
Also known as disk mirroring, RAID 1 is a method of producing fault tolerance by writing all data simultaneously to two separate drives. If one drive fails, the other contains all of the data, and it will become the primary drive. Disk mirroring doesn’t help access speed, however, and the cost is double that of a single drive. If a separate host adapter is used for the second drive, the term duplexing is attributed to RAID 1. Only two drives can be used in a RAID 1 array.
RAID 5
RAID 5 combines the benefits of both RAID 0 and RAID 1, creating a redundant striped volume set. Sometimes you will hear it called a stripe set with parity. Unlike RAID 1, however, RAID 5 does not employ mirroring for redundancy. Each stripe places data on n-1 disks, and parity computed from the data is placed on the remaining disk. The parity is interleaved across all the drives in the array so that neighboring stripes have parity on different disks. If one drive fails, the parity information for the stripes that lost data can be used with the remaining data from the working drives to derive what was on the failed drive and to rebuild the set once the drive is replaced.
RAID 10
Also known as RAID 1+0, RAID 10 adds fault tolerance to RAID 0 through the RAID 1 mirroring of each disk in the RAID 0 striped set. Its inverse, known as RAID 0+1, mirrors a complete striped set to another striped set just like it. Both of these implementations require a minimum of four drives and, because of the RAID 1 component, use half of your purchased storage space for mirroring.
What are Hot-Swappable Devices ?
Hot-swappable devices can be removed while the power to the system is still on. Warm-swappable devices need to be stopped in the operating system before being removed. The term has nothing to do with the heat level of the device.
Hard Drive Form Factors:
2.5” and 3.5”
Removable Storage:
Flash Drives, Memory Cards, Optical Drives
Power Outlet inputs:
Input 115V vs. 220V
