2. 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 Slot
flash ROM and CMOS RAM
3. Read-Only Memory Read-Write Memory
• non-volatile • volatile
Volatile Memory losses contents when power is
removed
PROM
EPROM
EEPROM
EAROM
Flash CAMDAM SAM
5. 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
6. 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
7. 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
8. SIMMs
Single Inline Memory Module
Pins on opposite sides form a single set of
contacts
1987
9. 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
10. 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
11. 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.
ECC/
Registered
DIMM
Non-ECC/
Non-Registered
DIMM
12. SDRAM
SDRAM PC66 transfer 533MB/s at 66Mhz
SDRAM PC100 Desktop Memory transfer 800MB/s at 100Mhz
SDRAM PC100 Server Memory (ECC) transfer 800MB/s at 100Mhz
SDRAM PC133 Desktop Memory transfer 1,066MB/s at 133 Mhz
SDRAM PC133 Server Memory (ECC) transfer 1,066MB/s at 133 Mhz
1999
19. Figure -Timeline of memory technologies based on Standard Organization
• Goal of new technology
o Increase overall throughput while retaining accuracy
o RAM manufacturers continue to produce older RAM
20. Cl or CAS rating
Over Clocking
Nomenclature(Identification of module)
Ranking
Comparison of DDR module notch
21.
22.
23.
24.
25. SGRAM
Synchronous 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
26. 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
27.
28. Virtual Memory
Virtual memory takes the place of RAM
memory
You should have a 2:1 ratio of RAM to
Virtual Memory
