Module 3 Flashcards
Virtual memory
If there is not enough system RAM, the memory space can be extended using disk storage
This is swap space
Total amount of addressable memory (system RAm plus swap space) is referred to as virtual memory/RAM
What is virtual memory
Area on hard disk which can hold pages of memory
Data and programs can only be used when moved to RAM
RAM types
DRAM
SDRAM
DDR SDRAM
DRAM
Needs constant refreshing
Without refreshing, the data in memory disappears
SDRAM
Older technology
Synchronised to system clock
DDR SDRAM
Double data rate
How many bits its in a byte
8
DDR 3 maximum size
16 GBs
DDR 4 maximum size
64 GBs
DDR 5
128 GBs
Memory module
A printed circuit board that holds a group of memory chips that act as a single unit
DIMM
Packaging for system memory
Different pin configurations for different RAM types
Where are memory modules located
In slots on motherboard
Are memory modules removable and replaceable
Yes
No of pins on DDR3
240
No of pins on DDR4
288
SODIMM
Memory that is Half the size of DIMMS
Comes ion 32- or 64-bit data paths
Found in laptops/imac
Laptop RAM
Single channel memory
Memory with one 64-bit bus between the CPU and RAM
Dual channel memory
Memory controller with 2 pathways to CPU- 128-bits of data transferred
Remember the motherboard has to be able to support dual,triple etc
For dual, triple, quad channels to work
Motherboard and DIMM must support the technology
Motherboard manufacturer colour-codes DIMM slots to shown you how to configure channeling
Setting up dual channeling
Pair of DIMMS in a channel must be equally matched din size speed ad features
Use same manufacturer ( recommended)
Setting up triple channeling
3 DIMMS populated with 3 matching DDR3 DIMMS
Which DDRs DIMMS can use dual channel
ALL DIMMS
Which DIMMS can use triple channel
ONLY DDR3
Which DIMMS can use quad channels
DDR 3, 4 and 5
Memory compatibility issues
DIMM format must match the motherboard
Most vendors recommend installing the largest module inn the lowest numbered slot
Modules from different vendors can be mixed-could cause problems
For best performance modules should be the same speed
Different speeds can be mixed but lowest speed will be used
Why is synchronous DRAM so-called
Works at the same speed as the motherboard
Configuring a system with dual channel memory. 2 modules and 4 slots. Which slots do you use?
Check system guide
How is laptop system memory packages
SODIMM
Additional memory was installed in a user’s system, now it won’t reboot. What should you do
Verify correct memory type was installed on the system and in the correct configuration
Check that the new memory module is seated properly in its slot. Try swapping memory around in the memory slots.
