Post on 01-Jul-2015
description
INTRODUCTIONto Memory(RAM)
By Jatin Goyal
Computer memory
Questions in Mind?
3. What are Upgrade limitation of system?
1.What is Computer memory and Why Do We Need It?
2. What are the Type of Computer memory and how they compared?
4. What they mean by multiple channel memory?5. How to identify memory of pc?
RAM Slotflash ROM and CMOS RAM
PRAM
Classification by access
Read-Only Memory Read-Write Memory
• non-volatile • volatile
Volatile Memory losses contents when power is removed
PROM
EPROM
EEPROM
EAROM
Flash CAMDAM SAM
Read-Write Memory
DAM SAM CAM
SRAM DRAM
SIMM DIMM DDR DDR2 DDR3
RAM
PRAM
Read-Write Memory
DAM (Direct Access Memory) - direct access to all memory cells - RAM
SAM (Sequential Access Memory) - data reading in sequence - HDD, optical discs
CAM (Content Addressable Memory) - associative memory - returns value according to
supplied word
The computer can access information held anywhere in RAM by addressing that part of the RAM directly.
e.g if information stored in the 1000th location in memory the system does not have to read the information in the preceding 999 locations to get there, instead it can access the 1000th location simply by specifying it.
RAM (Random Access Memory) Holds data and instructions used by CPU any piece of data can be returned in a
constant time
RAM
SRAM (Static Random Access Memory)- volatile
-does not need to be periodically refreshed- more complex internal structure, more
expensive, less capacity than DRAM
DRAM (Dynamic Random Access Memory)-volatile -to keep information must be periodically
refreshed- structural simplicity, high capacity
PRAM( phase change memory )-non-volatiles
Physical type of memory(DRAM)
SIMMs Single Inline Memory Module Pins on opposite sides form a single set of
contacts
1987
EDO DRAM
EDO = Extended Data Out Resides on SIMMs Sends and receives data
simultaneously Maximum transfer rate to L2 cache is
approximately 264 megabytes per second.
1990
DIMM(dual in-line memory module)
Small Outline DIMM(SO-DIMM)DIMM mean module has Ics or chips and connection b/w both side in single line.
DIMMs 1993
Buffered memory put less strain on the electrical load in Memory controller allowing a stable System that has several memory module.
ECC code ability to detect and correct the error during data
transmission.
Non-ECC/Non-Registered DIMM
ECC/Registered DIMM
Non-ECC/Non-Registered DIMM
SDRAM
SDRAM PC66 transfer 533MB/s at 66MhzSDRAM PC100 Desktop Memory transfer 800MB/s at 100MhzSDRAM PC100 Server Memory (ECC) transfer 800MB/s at 100MhzSDRAM PC133 Desktop Memory transfer 1,066MB/s at 133 MhzSDRAM PC133 Server Memory (ECC) transfer 1,066MB/s at 133 Mhz
1999
DDR 2 2006
DDR 3
within the module and has the added advantage of a 30% reduction in power consumption dropping the voltage from 1.8V to 1.5V
2010
DDR 4(future) 2015
Figure -Timeline of memory technologies based on Standard Organization• Goal of new technology
o Increase overall throughput while retaining accuracyo RAM manufacturers continue to produce older RAM
CURRENT TIME LINE OF MEMORY MODULE
Cl or CAS rating Over Clocking Nomenclature(Identification of module) Ranking Comparison of DDR module notch
CERTAIN TERM
SGRAMSynchronous Graphics RAM
SGRAM is a variant of SDRAM SGRAM makes use of block-writes to
increase video processing speeds. SGRAM is single-ported so the CPU
cannot write to it at the same time the image is being refreshed.
SGRAM is used in high-end graphics cards
How Many & What Kind of Memory Modules Are CurrentlyInstalled ?
Open the case and look at memory slots How many slots? How many filled? Review module imprint
Examine module for physical size and notch position
Read motherboard documentation See if board supports dual channels or triple
channels Last resort
Take motherboard and old memory modules to a good computer parts store for conformation
Speccy
Virtual Memory
Virtual memory takes the place of RAM memory
You should have a 2:1 ratio of RAM to Virtual Memory
Modifying Virtual Memory in Windows 8
Major Manufacturers
• Corsair Memory• Crucial
Technology• EDGE Tech Corp• GEIL• G.Skill• Hynix• Infineon
Technologies
• Kingston Technologies
• Micron Technology
• PNY• OCZ Technology• Rambus• Samsung• SimpleTech