Cooling: The cooling methods used in PCs range from simple fan exhaust to pump out hot air to complicated systems like Heat pipes and Peltier coolers.
Heat sinks: Fans may not be sufficient to cool the computer system where the computer is housed with high power processors. In such cases heat sinks are attached to the processor using conductive thermal compound to distribute the heat in the surroundings. Here, the heat is radiated using convection from hot surface to cooler surroundings.
Heat pipes: If the heat generated in the computer is high enough that the heat sinks are unable to cool the devices sufficiently, it may be necessary to cool the devices using fluids. Heat pipes are small tubes, built into cooling fins, that are filled with thermally conductive fluid. On heat absorption, the fluid vaporizes. The vaporized fluid gets transferred to a different part of the system, and condensed.
Peltier coolers: A Peltier device is an electronic component that gets colder whn an voltage is applied. The method is more suitable if the ambient temperatures inside the computer are high, and other methods of cooling are inefficient.
Baffle/shroud: A baffle/shroud is a plastic or metal conduit that directs air to (or from) a CPU or any other heat producing device for cooling the device. In the server room or data-center, baffles may be deployed to channel the air in a desirable fashion as well.
In row cooling, a dedicated cooling unit is placed within the row of racks. This unit cools all the racks in the row.
1. Active cooling uses a fan directly mounted onto the heat-sink for forced-air cooling.
2. Example: Case fan refers to a computer fan is any fan inside, or attached to, a computer case used for active cooling, and may refer to fans that draw cooler air into the case from the outside, expel warm air from inside, or move air across a heat sink to cool a particular component.
3. Passive cooling does not use a fan or other means of forced-air cooling. Passive cooling relies on natural convection cooling.
4. Pseudo-passive cooling does not use a fan mounted directly onto the heat-sink but does use forced air cooling from a nearby fan. May incorporate a fan duct or shroud.
Plug types:
NEMA plug: These connectors are power plugs and receptacles used for AC mains electricity in North America and other countries that use the standards set by the US National Electrical Manufacturers Association (NEMA).
Edison plug: An ordinary household electrical plug in the United States. Characterized by having two flat blades and a semi-round ground pin. Grounded connector will have three pins and ungrounded connector will have only 2 pins, and the earthing pin will be missing.
Twist lock: Twist-locking connectors refer to NEMA locking connectors. The plug is pushed into the receptacle and turned, causing the now-rotated blades to latch. See figure below: