Comptia A Ch.6 Flashcards
access time
The amount of time it takes to retrieve data from memory or a device.
cache memory
Designed to increase microprocessor operations.
CL rating
The amount of time (clock cycles) that passes before the processor moves on to the next memory address. Chips with lower access times (CL rating) are faster than those with higher access times (larger numbers).
CompactFlash (CF)
A type of removable flash memory storage that can be inserted into many devices, such as disk drives, cameras, PDAs, mobile phones, and tablet PCs.
DDR (double data rate)
Data is transmitted on both sides of the clock signal and uses 184 pins. Sometimes called DDR SDRAM or DDR RAM.
DDR2 (double data rate 2)
An upgrade to the DDR SDRAM standard and sometimes is called DDR2 RAM. It includes the following modules—DDR2-400, DDR2-533, DDR2-667, DDR2-800, and DDR2-1000. DDR2 uses 240-pin DIMMs and is not compatible with DDR; however, the higher-end (faster) DDR2 modules are backward compatible with the slower DDR2 modules.
DDR3 (double data rate 3)
An upgrade from DDR2 for speeds up to 1600MHz that better supports dual- and quad-core processor-based systems.
DDR3L
A DDR3 module that runs at a lower voltage (1.35V) than the 1.5V or higher DDR/DDR2/DDR3 modules. Less voltages means less heat and less power consumed.
DIMM (dual in-line memory module)
A style of 168-, 184-, or 240-pin memory chip normally used for RAM chips on Pentium and higher motherboards.
double-sided memory
A single memory module that contains two memory modules in one container (two banks). Data is still sent to the CPU 64 bits at a time. Some use the terms single-sided and double-sided to describe memory modules that have chips on one side (single-sided) or both sides (double-sided). Another name is double-ranked memory.
DRAM (dynamic random-access memory)
One of two major RAM types that is less expensive but also slower than SRAM. DRAM requires periodic refreshing of the electrical charges holding the 1s and 0s.
dual-channel
A system in which the motherboard memory controller chip handles processing of memory requests more efficiently by handling two memory paths simultaneously.
dual-voltage memory
Motherboard memory modules that operate at the 1.35V level that use less power and produce less heat. All memory modules must be 1.35V modules to operate at 1.35 volts.
ECC (error correcting code)
Uses a mathematical algorithm to verify data accuracy. ECC is more expensive than parity and the motherboard or memory controllers must also have additional circuitry to process ECC.
flash memory
A type of nonvolatile memory that holds data when the power is off.
fully buffered memory
A technology used in network server memory that requires a special memory controller sometimes advertised as FBDIMMs.
microSD
A storage device with nonvolatile flash memory used for mobile devices
miniSD
A storage device with nonvolatile flash memory used for mobile devices.
non-parity
A type of memory chip that is cheaper and does not do error checking.
PAE (physical address extension)
A feature provided by Intel that allows up to 64GB of physical memory to be used for motherboards that support it.
pages
In Windows disk caching, a 4KB block of memory space. The operating system swaps or pages the application to and from the temporary swap file as needed if RAM is not large enough to handle the application.
parity
A method of checking data accuracy.
Performance utility
A utility that monitors memory and other hardware parameters usage aspects.
RAM (random-access memory)
A volatile type of memory that loses its data when power to the computer is shut off.
RDRAM
Proprietary memory developed by Rambus, Inc
refresh (process)
A rewrite of the information inside memory chips.
registered memory
Memory modules that have extra chips (registers) near the bottom of the module that delay all data transfers by one clock tick to ensure accuracy.
quadruple-channel
A memory type in which a motherboard can access four memory modules simultaneously
SD (Secure Digital)
A storage device with nonvolatile flash memory used for mobile devices.
SDRAM (synchronous DRAM)
Provides very fast burst memory access by placing new memory addresses on the address bus before prior memory address retrieval and execution completes. SDRAM synchronizes its operation with the CPU clock signal to speed up memory access
SIMM (single in-line memory modules)
An older type of motherboard memory chip/module using either 30-pin and 72-pin connectors.
single-sided memory
A memory module that the CPU accesses at one time. The module has one “bank” of memory and 64 bits are transferred out of the memory module to the CPU. More appropriately called single-banked memory. Note that the memory module may or may not have all of its “chips” on one side.
SO-DIMM (small-outline DIMM)
A special small DIMM used in laptop computers
SPD (serial presence detect)
An extra EEPROM feature that allows the system BIOS to read the EEPROM (which contains memory information such as capacity, voltage, error detection, refresh rates, data width, etc.) and adjust motherboard timings for best CPU to RAM performance
SRAM (static random-access memory)
Memory that is faster but more expensive than DRAM. SRAM is also known as cache memory, or L2 cache.
swap file
A temporary file in hard disk space used by Windows that varies in size depending on the amount of RAM installed, available hard drive space, and the amount of memory needed to run the application.
triple-channel
A type of memory execution in which motherboards access three memory modules simultaneously
unbuffered memory
Memory that does not delay all data transfers by one clock tick to ensure accuracy as registered memory does. Used in low- to medium-powered computers.
USB flash drive
Sometimes called a flash drive or a memory stick, a drive that allows storage via a USB port.
virtual machine
A way for an operating system to appear as a separate computer to each application. One computer that has two or more operating systems installed that are unaware of each other due to virtualization software.
virtual memory
A method of simulating extra memory by using the hard disk space as if it were RAM.
Windows Memory Diagnostics Tool
troubleshooting memory problems with windows
xD
A storage device with nonvolatile Flash memory used for mobile devices.
