Compatibility of RAM with the system

The second most important thing everyone needs to keep in mind is whether the RAM he/she is going to buy will actually work with the system or will it get burned as soon as it is installed. You can be sure of the compatibility of RAM with the system by a very simple test. Just locate your motherboard manual (printed or online) and see what type and speed of RAM's are safe to use with the motherboard.
The motherboard documentation will usually include the following types of specifications:

• Memory Type: DDR3 1600/1333 MHz
• This means you can ONLY use a RAM of the type DDR3.
• This also implies that you will be safe to use RAM's with the speed of either 1600 or 1333 MHz. The rest of them might not work or might get burned in due course.

• Max Memory Size: 32 GB
• This specification specifies the maximum amount of memory you can install in your system without causing any harm to it.
• You are safe to use lesser amount of RAM than specified if you want or if you are on a tight budget, but make sure you do not exceed this limit.

You should also calculate the maximum RAM supported per slot by the motherboard by dividing the Max Memory Size by the number of sockets present on the motherboard.
For example, in a system with four RAM slots, you can install an 8 GB chip in each slot for a 32 GB motherboard.
However, in a system with eight slots, you can install 4 GB chips in each slot for a 32 GB motherboard. Using a chip with a higher memory size like 8 GB ones in this case will not be beneficial for your system.

Dynamic RAM: modules

DRAM packages are in turn often assembled into plug-in modules for easier handling. Some standard module types in order of increasing speeds are:

-DIP(Dual in-line Package) 16-pin (chip)

-SIPP(Single In-line Pin Package) (usually FPRAM)

-SIMM(Single In-line Memory Module) 30-pin (usually FPRAM)

-SIMM 72-pin (often EDO RAM)

-DIMM(Dual In-line Memory Module) 168-pin (SDRAM: Synchronous DRAM)

-DIMM 184-pin (DDR SDRAM: Double Data Rate SDRAM)

-RIMM(Rambus In-line Memory Module) 184-pin (RDRAM: Rambus DRAM)

-DIMM 240-pin (DDR2 SDRAM / DDR3 SDRAM)

Dynamic RAM: more info

Dynamic random-access memory (DRAM) is a type of random-access memory (RAM) that stores each bit of data in a separate capacitor within an integrated circuit. The capacitor can be either charged or discharged; these two states are taken to represent the two values of a bit, conventionally called 0 and 1.

DRAM is volatile memory, since it loses its data quickly when power is removed. The transistors and capacitors used are extremely small; hundreds of billions can fit on a single memory chip.

Dynamic random access memory is produced as integrated circuits bonded and mounted into plastic packages with metal pins for connection to control signals and buses.

Today, these DRAM packages are in turn often assembled into plug-in modules that are installed into RAM sockets in the motherboard for easier handling.

DRAM is usually arranged in a square array of one capacitor and transistor per data bit storage cell. Typically, manufacturers specify that each row must have its storage cell capacitors refreshed every 64 ms or less. Refresh logic is provided in a DRAM controller which automates the periodic refresh, so no software or other hardware has to perform it. This makes the controller's logic circuit more complicated, but this drawback is outweighed by the fact that DRAM is much cheaper per storage cell and because each storage cell is very simple, DRAM has much greater capacity per geographic area than SRAM.