Installing, Configuring, and Troubleshooting Storage Devices Flashcards
What is system memory
The main storage area for programs and data when the computer is running.
What is RAM
(random access memory) The principal storage space for computer data and program instructions.
What is a volatile memory
A type of memory where data cannot be stored without power being supplied.
Definition of virtual memory
An area on the hard disk is allocated to contain pages of memory.
Defintion of DRAM
A type of volatile memory that stores each bit of data as a charge within a single transistor.
Definition of SDRAM
A variant on the DRAM chip is designed to run at the speed of the system clock, thus accelerating the periodic refresh cycle times.
What does do DRAM in a PC
Stores each data bit as an electrical charge within a single bit cell.
Bit cell is composed of a capacitor and a transistor.
The charge dissipates, causing the memory to lose information.
Dynamic memory has to be refreshed to keep the information.
What does do SDRAM in PC
Older technology.
Synchronized to the system clock.
What is DDR SDRAM
The standard for SDRAM is where data is transferred twice per clock cycle.
Examples of DDR Standards
Examples of DDR Standards:
DDR2 – 1066/PC28500:
Memory works at 266 MHz, bus works at 533 MHz.
The double data rate gives 1066 MT/s.
Nominal transfer rate of 8.533 Gbps.
DDR3 – 1600/PC321800:
Memory works at 200 MHz, bus works at 800 MHz.
The double data rate gives 1600 MT/s.
Nominal transfer rate of 12.8 Gbps.
DDR4 – 1600/PC4-12800:
Memory works at 200 MHz, bus works at 800 MHz.
The double data rate gives 1600 MT/s.
Nominal transfer rate of 12.8 Gbps.
Lower voltage, so less power consumption than DDR3.
DDR4 – 2400/PC4-19200: Memory works at 300 MHz, bus works at 1200 MHz. The double data rate gives 2400 MT/s. Nominal transfer rate of 19.2 Gbps. Faster than any DDR3.
Definition of a Memory Module
A printed circuit board that holds a group of memory chips that act as a single unit.
What is DIMM
(dual inline memory module) Standard packaging for system memory. There are different pin configurations for different RAM types.
Where is the Memory Module located
Located in slots on the motherboard.
True or False
Memory Modules are not removable and replaceable
False
Memory Modules are removable and replaceable
How are Memory Modules defined
Defined by their design and by the number and type
of chips contained.
What are the pins and voltage for these RAM Types: DDR DDR2 DDR3 DDR4
RAM Type
DDR: (voltage: 2.5 to 2.6 V) (pins: 184)
DDR2: (voltage: 1.8 to 1.9 V) (pins: 240)
DDR3: (voltage: 1.35 to 1.5 V) (pins: 240)
DDR4: (voltage: 1.2 V) (pins: 288)
Definition of SODIMM
Memory that is half the size of DIMMs, is available in 32- or 64-bit data paths, and is commonly found in laptops and iMac systems.
In what computer system does SODIMM occur.
Laptop RAM
What RAM type does SODIMM have the same amount of pins.
DDR and DDR2 have the same number of pins, but the key position is different.
How does SODIMM typically fit into a slot
Typically fits into slots that pop up at a
45º angle to allow the chips to be inserted or removed.
What are the pin packages for SODIMM?
Pins:
DDR 200 pin packages.
DDR2 200 pin packages.
DDR3 204 pin packages.
DDR4 260 pin packages.
The definition of single-channel memory?
Memory with one 64-bit bus between the CPU and RAM.
The definition of dual-channel memory?
Memory controller with two pathways to the CPU, enabling 128 bits of data transferred per transaction.
How many pathways does a memory module have?
Effectively two pathways through the bus to the CPU.
How many bits does a memory module have?
128 bits of data can be transferred per transaction.
What should memory modules be identical in?
Speed Capacity Chip number Density Location
Definition of Parity Checking
An error-checking method where each byte of data in memory is accompanied by a ninth bit is used to check for corrupted data.
Definition of Nonparity
The system memory does not perform error checking.
Definition of ECC memory
RAM with built-in error correction security.
What is Parity Checking
Uses 8 bits for memory and 1 bit to check parity.
Old technology is rarely if ever used now.
True or False
Most desktops now use non-parity memory.
True
True or False
Systems that require a high level of reliability use ECC memory.
True
What does ECC memory
ECC memory has an extra chip and a 72-bit data bus.
True or False
The motherboard must support the use of ECC memory modules.
True
True or False
Can mix ECC and non-ECC modules.
False
Cannot mix ECC and non-ECC modules.
True Or False
The DIMM format must match the motherboard.
True
What do most vendors recommend when installing memory modules
Most vendors recommend installing the largest module in the lowest numbered slot.
True or False
Memory modules from different vendors can’t be mixed
False
Memory modules from different vendors can be mixed
What needs to be done to increase bus speed?
Purchasing a new motherboard and memory modules (and possibly CPU).
Memory Module:
If the motherboard supports an upgrade but the system is not configured to use it, what needs to be done?
Enable a dual-channel configuration.
For best performance and reliability on a PC
Configure multi-channel systems with identical memory modules for each channel.
True or False
ECC memory cannot be mixed with non-parity memory and must be supported by the motherboard.
True
True or False
Registered memory cannot be mixed with unbuffered modules and must be supported by the motherboard.
True
Definition of Mass Storage Devices
Mass storage devices: Non-volatile storage devices that are able to hold data when the system is powered off.
Give all the ways mass storage devices, store data.
Magnetic
Optical
Solid-state
True or False
Cannot hold data when the system is powered off.
False
Can Hold data when the system is powered off.
True or False
Hold data when the system is powered off.
True
Definition of HDD (hard disk drive)
HDD: (hard disk drive) A device that provides persistent mass storage for a PC.
What does a workstation typically store
OS files.
Application program files.
Drivers.
User data.
True or False
HDD is the primary persistent storage method.
True
Definition of Tracks
Tracks: Data written as concentric rings on a disk drive.
Definition of Cylinders
Cylinders: The aggregate of all tracks that reside in the same location on every disk surface.
How much TB does HDD go up too
8 TB
Where is data stored on an HDD
Data is stored on metal or glass platters coated with magnetic substances.
What does each platter on an HDD have?
Top and bottom read/write heads.
Heads that float above platters.
What are the form factors and heights for platters of HDD?
Form factors include 3.5” and 2.5”.
Height varies 15 mm, 9.5 mm, 7 mm, and 5 mm.
HDD Performance Factors:
Definition of Acces Time
Access time: Speed at which memory or a disk drive can be addressed and utilized.
HDD Performance Factors:
Definition of Internal Transfer Rate
Internal transfer rate: Measure of how fast read/write operations are performed on the disk platters.
HDD Performance Factors:
Definition of External Transfer Rate
External transfer rate: Measure of how fast data can be transferred to the CPU across the bus.
HDD Performance Factors:
Definition of Early Failure Rate
Early-life Failure Rate: A method of calculating how quickly a device will fail through accelerated testing.
HDD Performance Factors:
Definition of MBTF
MBTF: (mean time between failures) The rating on a device or component that predicts the expected time between failures.
HDD Performance Factors:
Definition of Life Expectancy
Life expectancy: The length of time for which a device can be expected to remain reliable.
HDD Performance Factors:
Definition of S.M.A.R.T
S.M.A.R.T.: Technology designed to alert the user to possible hard disk failures before the disk becomes unusable.
Definition of HBA
HBA: (host bus adapter) A component that allows storage devices to exchange data with a computer system by using a particular interface.
Definition of Drive Controller
Drive controller: The circuitry in the disk unit that allows it to put data on the bus, which the HBA shuttles to the CPU or RAM.
Give all features of HBA
Connection point for internal mass storage devices.
The interface between drive, HBA, rest of the system is a type of bus.
Old technology included PATA and SCSI.
Most systems now use SATA.
Definition of SATA
SATA: A widely used hard disk interface using a 7-pin data connector and a 15-pin power connector.
Give all features of SATA
Transfers data in serial format.
Cables can be up to 1 m and are thin and flexible.
Cables terminate with 7-pin connectors.
Each host adapter port supports a single device.
Drives are hot-swappable.
Give all SATA speeds of SATA, SATA 2, and SATA 3
Original SATA: up to 1.5 Gbps.
SATA 2: up to 3 Gbps.
SATA 3: up to 6 Gbps.
Definition of SSD
SSD: (solid-state drive) A personal computer storage device that stores data in non-volatile special memory instead of on disks or tape.
What are the advantages of SSD
Advantages: No moving parts. Quieter and more power-efficient than HDD. Less prone to failure due to shock. Better read times: Seek time is faster. File fragmentation is eliminated. Less likely to lose data due to power failures.
What are the disadvantages of SSD
Disadvantage:
High cost.
SSD Interfaces and Form Factors:
Definition of AHCI
AHCI: (Advanced Host Controller Interface) A logical interface used by SATA drives to communicate with the bus.
SSD Interfaces and Form Factors:
Definition of NVMHCI
NVMHCI: (Non-Volatile Memory Host Controller Interface Specification) A logical interface used by PCIe-based SSD drives to communicate with the bus.
SSD Interfaces and Form Factors:
Definition of NVMe
NVMe: (NVM Express) An interface for connecting flash memory devices, such as SSDs, directly to a PCI Express bus.
SSD Interfaces and Form Factors:
Definition of Lanes
Lanes: In PCIe, two-wire pairs (four wires in total) using low voltage differential signaling, with one pair used to transmit and the other pair to receive (bi-directional).
