Memory Technology Flashcards
random access memory
hold data and instructions used by the cpu
DRAM
dynamic ram- memory modules used on motherboard
Variations of DRAM
DIMM- dual inline memory module. small outline DIMM (SO-DIMM)-Laptops. microDIMMS- subnotebook comps. RIMM + SIMM (outdated)
Diiference between DRAMs
-data path width each module accommodates. -how data moves from system bus to module
types memory modules
288 pin ddr4- fastest dimm, low voltage, can support quad, dual, and single dimm. 240 pin ddr3- supports quad, triple, dual, single dimm. 240p ddr2. supports dual channel or function as single. 184p ddr supports dual or fuctions as single dimm 168p sdram. RIMM 184 pin-
DIMM details
64-bit data path. independent pins on opposite sides of the module. older DIMMs- doesnt not perform simultaneously with others. synchronous DRAM- runs syncroniusly with system bus. 2 notches, 168 pins
What is the typical access time for a register?
1 nanosecond
What is the typical access time for a cache?
2 nanoseconds
What is the typical access time for main memory?
10 nanoseconds
What is the typical access time for magnetic disk?
10 milliseconds
What is the typical access time for magnetic tape?
100 seconds
What is the capacity of a register?
<1kb
What is the capacity of main memory?
64-512mb
What is the capacity of a cache?
1mb
What is the capacity of a magnetic disk?
5-50gb
What is the capacity of a magnetic tape?
20-100gb
SDRAM
Synchronous Dynamic Random Access Memory Runs synchronously with system bus Two notches Uses 168 pins
DIMM has ____ ____ on opposite sides of module
independent pins
Double Data Rate
also called ddr sdram- two times faster than sdram. ddr2 sdram- faster uses less power. ddr3 sdam- faster ddr2, uses less power. ddr2 and 3- 240 pin-not compatable uses different notches
DDR
Double Data Rate Twice as fast
What factors effect the performance, capacity, and features of DIMMs?
Number of channels they use How much RAM is on one DIMM Speed Error checking abilities Buffering
DDR3
Twice as fast as DDR2, uses less power
What does dual channel memory control do?
Memory controller communicates with two DIMMs at the same time Doubles memory access speed
factors affect capacity, features and performance of DIMMs
number of channels they used. how much ram is on one dimm. speed, error detection, buffering
quad channeling
introduced with intel sandy brings chipset and processor. introduced 8 memory slots
setting up for dual channeling
pair of dimms in channel must be equally matched: eg speed, size, manufacturers and features
setting up for triple dimm channeling
3 DIMM slots populated witg 3 matching ddr3 dimms. 4th is empty
What DIMMs use dual channels?
DDR, DDR2, DDR3 DDR3 also uses triple channel
What does dual channel memory control do?
Memory controller communicates with two DIMMs at the same time Doubles memory access speed
What did the Intel Sandy Bridge chipset and processor introduce?
Quad channelling using 8 memory slots The processor can access 4 slots at a time
How do you set up dual/triple channeling?
Your pair (or set of 3) DIMMs in a channel must be identical in size, speed, and features (it also helps if they’re the same manufacturer).
What is DIMM speed measured in?
MHz and PC Rating
What are the PC Ratings?
Total bandwidth between module and CPU: DDR2 usually PC2 DDR3 usually PC3 DDR4 usually PC4
What are the steps to installing a DIMM?
Pull out supporting arms on the sides of the slot Use notches on DIMM edge connector as a guide Insert DIMM straight down into the slot Ensure supporting arms lock into position
If new memory is not recognized try _______
Resetting the module
What happens if you mix buffered memory with unbuffered memory?
It won’t work lol
Installing DIMM: Motherboard using DDR3 dual channel DIMMs
Install matching DIMMs in 2 blue slots Install matching DIMMs in 2 black slots
Installing DIMM: Motherboard using DDR3 triple channel DIMMs
Install matching DIMMs in 3 blue slots If 4th spot is populated it reverts to single channelling For dual channeling, install 2 matching DIMMs in blue spots furthest away from processor
What are the minimum and maximum RAM requirements for Windows 7/8?
Minimum RAM is 2GB Windows 7 64 bit max RAM 16GB Windows 8 64 bit max RAM 128GB
What do you have to consider when looking at purchasing memory?
Total RAM installed Memory technology used Speed of memory in MHz, PC rating, or ns ECC or non-ECC CL or RL rating Single, dual, triple or quad channeling
What are the connectors inside memory slots made of?
Tin or gold
What types of memory are used in laptops?
DDR, DDR3L, DDR3, DDR4, or DDR2 SO-DIMM
CAS and RAS
Column Access Strobe Row Access Strobe
What are column access strobe (CAS) and row access strobe (RAS)?
The number of clock cycles it takes to write or read a column or row of data off a memory module. CAS is more common.
Fastest memory with lowest voltage requirements?
288-pin DDR4 DIMM
Here, have a chart:
