Chapter 4 - RAM Flashcards
When data or programs are not being used, where are they stored?
In the HDD or SSD
When data or programs are in use, where are they moved?
A copy is sent from mass storage to RAM and runs
As CPUs data bus increased, what need also increased? Where did DRAM chip move to?
The need for RAM wide enough to fill the bus. They moved from being directly on the motherboard, to circuit boards called stick/modules that we know today
When the CPU needs certain data, it requests it from?
it requests it from system memory (RAM) through the Memory Controller. The process typically works as follows:
CPU Request: The CPU generates a memory address for the data it needs. Address Bus: The memory address is sent from the CPU to the RAM via the address bus. Memory Controller: The memory controller (often part of the CPU in modern systems) coordinates the data retrieval. It locates the data in RAM and sends it back to the CPU over the data bus.
SDRAM
“Synchronous Dynamic Access Memory”
SDRAM is still DRAM, but is tied to the system clock.
Operates in sync with the processor’s clock cycles, enabling faster and predictable data access compared to asynchronous DRAM.
How it Works: It breaks data into smaller chunks and accesses it in bursts, reducing wait time by pre-fetching data.
DRAM
“Dynamic Access Memory”
Is a specific category of RAM (Random Access Memory). RAM is the general term for volatile memory, which temporarily stores data for quick access by a computer’s processor. DRAM is one of the two main types of RAM.
Needs to be constantly refreshed to retain data, as it stores data in capacitors that lose charge over time. It’s typically used as the main memory in computers because it’s cheaper and denser, which allows for more memory capacity.
RDRAM
“Ram Bus Dynamic Access Memory”
A type of DRAM designed by Rambus Inc. that offers higher bandwidth and faster speeds compared to traditional SDRAM
What is Throughput?
Throughput is the amount of data or tasks processed by a system in a given amount of time.
DDR2
DDR2 (Double Data Rate 2) is the second generation of DDR SDRAM, offering faster speeds and less power consumption
240 pin
200 SO-DIMM
DDR3
DDR3 (Double Data Rate 3) is the third generation of DDR SDRAM, which offers:
Higher speeds, architecture improvements, lower power usage
240 pins
204 SO-DIMM pins
DDR3L\DDR3U
versions of DDR3 that runs at lower voltage than standard DDR3. They are used in data centers because they generate less heat, which lowers cooling bills
DDR4
DDR4 (Double Data Rate 3) is the fourth generation of DDR SDRAM, which offers:
Higher density, lower voltage, and faster i/o speeds
288 pins
260 SO-DIMM pins
CAS Latency
CAS (“Column Array Strobe”) latency refers to the number of clock cycles memory delays before delivering data. Lower CL values are faster.
DDR4 (2014)
Higher density, lower voltage, faster I/O.
288 pin / 260 SO-DIMM.
Mega-transfers per second as opposed to MHz.
What types of memory do motherboards use?
Motherboards use buffered or unbuffered memory. Unbuffered memory is consumer RAM.
