Memory Flashcards
This deck refers to section 3.5 on Memory.
How does RAM differ from ROM?
Random Access Memory vs Read Only Memory
What is the difference between SRAM and DRAM?
DRAM: Dynamic Random Access Memory; uses transistors and capacitors and stores data in bits. Primarily used as system memory.
SRAM: Static Random Access Memory; uses switches; provides much faster access to data. Primarily used for cache. Costs roughly 10x as much as SRAM.
What are two advantages of using DDR3 memory over DDR2?
a
What are two places where the memory controller might be located in modern PC systems?
b
Why is consulting the motherboard documentation so important when purchasing memory?
v
You have DDR2 memory with a CAS latency of 6 and DDR3 memory with a CAS latency of 7. What can you tell about the relative speed of the two memory modules?
d
What is the difference between ECC and registered memory?
f
SDRAM: (Single Data Rate SDRAM)
Frequency of memory is synched with frequency frequency of system clock. Sends one command (instruction) per cycle, with one set (64-bits) of data per length. 3.3v @ 33-166 MHz
DDR SDRAM: (Double Data Rate Memory)
One command per cycle with TWO data sets. Twice the amount of data. 2.5v @ 100-200 MHz
DDR2 SDRAM:
Four data sets per clock cycle. 1.8v @ 200-533 MHz. Buffer between data bus and memory.
DDR3 SDRAM:
Eight data sets per clock cycle. 1.5v @ 400-1000 MHz. Buffer included.
RDRAM: Rambus RAM
Legacy version of post-DDR. Transfers data in 32 bits, 2 data sets per cycle. System must be configured with a continuity module in empty slots.
SIMM: Single Inline Memory Module
Obsolete term. Used for older memory.
DIMM: Dual Inline Memory Module
Any variation of DDR RAM.
SO-DIMM: Small Outline Dual Inline Memory Module
Used in laptops. Difference is only size. Capacity is the same, but number of sticks needed might be double.
