Memory Characteristics Flashcards
(23 cards)
What’s the first step when choosing memory of the PC system?
Determine the type of memory is supported by your PC
How can you determine the memory type for your system if documentations are missing
Use online resources like memory config or system scanners
What does the memory scanner tool do?
Analyze installed memory, speed, capacity, suggest compatible upgrades
What should you check if the PC cannot boot for a system scan?
Open the Case, checking the Ram modules, for the notch and pin configuration and search online using the serial numbers.
Why is visual inspection alone not enough to identify the type of Ram
Frequency and other operating specs can’t always be determined by sight.
What is a memory package or form?
The physical configuration of RAM such as DDR2, DDR3, or DDR4, matched to motherboard slots
What’s the memory limit for the 32 bit system without PAE?
4GB but often limited to 2GB or less depending on the motherboard
What is PAE and how does it affect 32bit memory limits?
Physical Address Extension; allow some 32bit system to use up to 64-128GB of RAM with compatible OS and CPU
How much memory can a 64 system theoretically address?
Up to 16 exabytes(EB) though most system support up to 1-2 TB
Why memory speed is important?
It must match the motherboard’s specs for optimal compatibility and performance.
What’s ECC memory?
Error-Correcting Code memory that detects and corrects internal data corruption mainly used in servers
How to identify the ECC memory?
ECC modules usually have 9 chips(or odd number Divided by 3 or 5), while non-ECC chips have 8.
Can ECC and non-ECC ram be used together?
No, mixing will disable the ECC functionality
What is registered (or Bufferred) memory?
Ram with buffer chip stabilize the large systems, mostly used in servers.
What’s CAS latency(CL)?
The delay in the clock cycles between a command and data availability. Lower is better
What does memory timing number like 5-5-5-15 represents
CAS Latency, tRCD(row to column delay), tRP(precharge time), and tRAS(Active to precharge).
WHat’s SPD(Serial Presence Detect)?
Info stored in the EEPROM on RAM, read by BIOS to auto-configure memory settings
Can you override SPD settings in BIOS? Why?
Yes, to tweak performance or improve system stability-but it may cause instability.
How to measure CAS Latency(CL)?
the delay between read request and data becoming available on the RAM output pin
What are the limits to how much total memory can one pc have?
Number of slots, max capacity per slot, motherboard total support, and os memory addressing limit.
Do all motherboards support double sided RAM with chips on only one side
No compatibility should be verified in documentation
whats the difference between single-sided and double sided ram
Single sided RAM has one logic bank; double sided has two, requiring the system to switch between them
Can you have a double sided ram with chips on only one side
Yes depends on the internal memory banks organization, not a chip replacement
