evolution of computer cooling systems final

8/6/2019 Evolution of Computer Cooling Systems FINAL

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The process of removing heat from computer

components.

Excess heat must be dissipated in order to keep

the components within their safe operating

temperatures.

Varied cooling methods are also used to

achieve greater performance such as

overclocking.


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Excessive heat can cause all sorts of problems.

Overheated parts generally exhibit a shorter

maximum life-span and may give problems

resulting in system freezes or crashes.

Manufacturers have given very close tolerancesfor operating temperature and humidity.


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Using vacuum tubes

Using transistors

Using integrated circuits

Using microprocessors


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Vacuum tubes

produce heat while

operating.

This waste heat is

one of the principal

factors that affect

tube life.UNIVAC - I


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Method of anode cooling.

Radiates the heat by black body

radiation from the anode to the glass

envelope.

Natural air circulation, convection, then

removes the heat from the envelope.


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forced air cooling

adding fins to the anode. operating the anode at red hot

temperatures.

Tubes with external anodes may be

cooled using forced air, water, vapor,

and multiphase.


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There was less heat

generated per circuit.

There was only narrow

tolerances to temperature

variations.

A transistor, also normally

used as a switch, could turn

on accidently, when

overheated, causing chaos

in the system.AKAT - 1


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Room air conditioning

became very important.

Most systems were installed

on false floors, with a spaceof about 1 meter or 3ft

below the floor.

This allowed the air

conditioning to be supplied

under the floor, and

exhausted through the

false ceiling

A typical Air conditioning unit for cooling server racks.


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Tape drives(storage device) were particularly

large producers of heat.

Tapes produce a lot of heat due to the

powerful motors they use.

tapes and disks to be installed in a separate

room, or partitioned off from the mainframe, so

that air conditioning requirements could be

better controlled.


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Amount of heat generated

by an integrated circuit is

the prime cause of heat

build up in modern

computers.

It is a function of the

efficiency of its design, the

technology used in its

construction and the

frequency and voltage at

which it operates.


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In operation, the temperature levels of a computer's

components will rise until the temperature gradientbetween the computer parts and their surroundings is

such that the rate at which heat is lost to the

surroundings is equal to the rate at which heat is

being produced by the electronic component, and

thus the temperature of the component

reaches equilibrium.

For reliable operation, the equilibrium temperature

must be sufficiently low for the structure of the

computer's circuits to survive.


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Air Cooling

Liquid Cooling

Heat Sinks


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The term computer

fan usually refers to fans

attached to a computer.

Most common areCPU fan, GPU fan, Chipset

fan, PSU fan, HDD fan

& PCI slot fans.

It basically allows airflow that

will help cooling.

Size varies from 40mm

240mm dia.


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Sufficient number offans will create aneutral airflow that

will keep thetemperature inside

the cabin undercontrol.

Positions of fans isimportant.


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Air is drawn in at the front of the

rack and exhausted at the rear

blade chassis - In contrast to the

horizontal orientation of flat

servers, blade chassis are often

oriented vertically. This vertical

orientation

facilitates convection.

When the air is heated by the

hot components, it tends to flow

to the top on its own, creating a

natural air flow along the

boards.


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Submerse the computer's

components in a thermally

conductive liquid.

Does not require any fans or

pumps.

cooled exclusively by passive

heat exchange between the

computer's parts, the cooling

fluid and the ambient air.


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Water has the ability to

dissipate more heat from

the parts being cooled

than the various types of

metals used in heatsinks.

Can be set up to cool

the CPU

, GPU

, and othercomponents at the

same time with the same

system.


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Involves attaching a block of

machined or extruded metal to the

part that needs cooling.

This block usually has fins and ridges to

increase its surface area.

The heat conductivity of metal is much

better than that of air.

Its ability to radiate heat is better than

that of the component part it is

protecting.


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Same principle as passive, with

the addition of a fan that is

directed to blow over or

through the heat sink.

The moving air increases the

rate at which the heat sink can

exchange heat with the

ambient air.

Primary method of cooling a

modern processor or graphics

card.


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A hollow tube containing a heat

transfer liquid.

As the liquid evaporates, it carries

heat to the cool end, where it

condenses and then returns to the

hot end.

Heat pipes thus have a much

higher effective thermal

conductivity than solid materials.

In computers, the heat sink on the

CPU is attached to a larger radiator

heat sink by a large heat pipe.


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Dust acting as a thermal insulator and impeding airflow,

thereby reducing heat sink and fan performance.

Poor airflow including turbulence due to friction against

impeding components, or improper orientation of fans,

can reduce the amount of air flowing through a case

and even create localised whirlpools of hot air in thecase

Poor heat transfer due to a lack of, or poor application

of thermal compounds.


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Thermoelectric Cooling

Liquid Nitrogen Cooling

Liquid Helium Cooling

Phase-Change Cooling


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Run parts of computer (such as the CPU and GPU) at

higher voltages and frequencies than manufacturer

specifications call for.

This can dramatically increase the performance of the

computer.

Results in a greater amount of heat generated and thus

increasing the risk of damage to components and/or

premature failure.

More advanced and expensive cooling systems are

required in these cases.


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As liquid nitrogen evaporates at -

-196 C, far below the freezing

point of water, it is valuable as

an extreme coolant for short

overclocking sessions.

CPU will usually expire within a

relatively short period of time due

to temperature stress caused by

changes in internal temperature.

Liquid helium, colder than liquid

nitrogen, has also been used for

cooling.


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Based on Peltier effect inverse of Seebeck effect.

Applying a voltage to a thermocouple creates a

temperature difference between two sides.

Modern TECs use several stacked units each

composed of dozens or hundreds of thermocouples

laid out next to each other, which allows for a

substantial amount of heat transfer.


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Uses a compressor of the same type as in a

window air conditioner.

Compressor compresses a gas (or mixture of gases)which condenses it into a liquid.

Liquid evaporates (changing phase), absorbing the

heat from the processor.

The evaporation can produce temperatures

reaching around 15 to -150 degrees Celsius


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Some laptop components, such as hard drives and optical

drives, are commonly cooled by having them make contact

with the computer's frame, increasing the surface area whichcan radiate and otherwise exchange heat.


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Practice of running the CPU or any other

component with voltages below the device

specifications.

An undervolted component draws less power and

thus produces less heat.


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evolution of computer cooling systems final

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