since their has been many different types of ram created over the years a unique notch insures that you can only use the correct type of ram that works with your motherboard.
DIMMs are the newer tech.
2.66" 189-pin SO-DIMM contains DDR SDRAM 2.66" 189-pin SO-DIMM contains DDR2 SDRAM 2.66" 145-pin SO-DIMM contains SDRAM 2.35" 40-pin SO-DIMMs (outdated) 130-pin SO-RIMM (conatains Rambus memory and has two notches).
Answering "What are four types of SO-DIMMs used in a notebook?"
While 184-pin DIMMs and 168-pin DIMMs are approximately the same size, 184-pin DIMMs have only one notch within the row of pins
rimms
Types of DIMMs are DDR3 and DDR2 that have 240 pins, DDR DIMMs with 184 pins and SDRAM DIMMs with 168 pins.
DDR SDRAM for laptops come ineither 200-pin SO-DIMMs or 172-pin micro-DIMMs
1 notch
open = 5 notches 1/4 = 4 notches 1/2 = 3 notches 3/4 = 2 notches full = 1 notch
Notches on the Choke TubeMost standard choke tubes have notches on their ends. The notches can be used to identity your choke tube, but they can be difficult to see. The following list shows what kind of choke the number of notches designate:1. One notch is a Full choke. (/)2. Two notches is an Improved Modified choke (//)3. Three notches is a Modified choke (///)4. Four notches is an Improved Cylinder choke (////)5. Five notches is a Skeet (or Cylinder) choke (/////)
ECC
Somalia africa