RAM, or random access memory, is the chip assemblies that store data for quick recall and require constant power. When selecting RAM, factors to consider include type, speed, quantity, quality, error detection, and physical module specifications. Common RAM types are SDRAM, DDR, DDR2, DDR3, and Rambus. To find the right RAM for a computer, check the manual or manufacturer website. General best practices for RAM installation include using the correct RAM for the motherboard, following all instructions, matching module speeds, starting with the lowest numbered slot, and checking RAM after installation.

1. RAM
Computer Maintenance

2. What is it?
• Chip assemblies that store data for
very quick recall. The main memory in
a computer requires constant power
to be able to hold data. Every task
performed by a computer requires the
program and data to be loaded into
memory.

3. Items to consider when selecting
memory for a computer:
• Type
• Speed
• Quantity
• Quality
• Error detection
• Physical module
size and pin
layout
• Single- or
double-sided
module

4. TYPES

5. SDRAM

6. DDR

7. DDR 2

8. DDR 3

9. Rambus

10. SoDIMM

11. MicroDIMM

12. Finding the Right Memory for a
Computer
• Check the computer
or motherboard
manual, the
manufacturer’s Web
site, or call the
manufacturer.
• Go to a memory
manufacturer’s Web
site such as Crucial’s
(crucial.com) access
the memory
upgrade, memory
search, or
“configurator”
program on the
homepage and enter
the requested
information.

13. Computer Reports the Wrong Amount
of Memory
• On some computers, the on-board video
uses a portion of the memory.
• Remember that one kilobyte is 1024 bytes,
and that one megabyte is 1024 kilobytes.
• Make sure the module is installed
correctly.
• Some motherboards have restrictions for
memory.
• You might have a bad memory module.

14. General Rules for Memory
Installation
• Use the correct memory for the motherboard.
• Follow all instructions from the computer
/motherboard and memory manufacturers.
• Make sure all the memory modules match.
(speed)
• Start at the lowest number memory slot, 0 or 1.
• Insert the memory in capacity order starting with
the highest-capacity module in the lowest
number slot.
• After you have installed the memory, boot the
computer and check the memory.