3.7 Summarize power supply types and features. Flashcards
The power supply provides ___ power voltages for use inside of your computer.
DC
Power supplies convert __ power to the __ power that computer components run on.
AC
DC
What is the significance of 115V vs. 220V input?
115V is used in North America, 220V is used abroad. Some power supplies may only support one or the other or have a switch to configure compatability.
What is the significance of 5V vs. 12V output?
They are the maximum power provided by the power supply connectors inside a PC to individual components.
This is the power available at a wall outlet.
AC (alternating current)
24-pin motherboard power adapter is keyed, what does this mean?
The connector is keyed so that it can only plug in one way, ensuring that the proper voltages are supplied to the right pins.
Specific pins are designated to supply 5V, 12V, or 3.3V.
___ is the total capacity of the power supply.
Wattage rating
What kind of current is output in wall outlets outside of North America?
220V AC
This must be high enough to meet the total power demands of all components in the computer.
Wattage rating
This must be high enough to meet the total power demands of all components in the computer.
Wattage rating
What may determine what wattage rating is needed for the power supply?
Number of components
Types of components
What may determine what wattage rating is needed for the power supply?
Number of components/device
Types of components/device
The type of case the computer is in also needs to be considered to ensure that the power supply…
physically fits properly, has long enough cables.
How do you determine the exact wattage requirement you need from your power supply?
Add all of the wattage ratings of the individual components.
Your power supply’s wattage must meet or preferably exceed that total value.
The connectors needed are determined by the connector types used on the devices to be powered. For example, if you have an older ATX motherboard, it has a 20-pin ____ connector, while newer models contain the 24-pin ___ connector thanks to the addition of the PCIe bus.
Molex
You should always disconnect from any power source when you’re working on any kind of device. You must also remember that some devices will store charge in ___. This charge could provide an electric shock, so you want to be sure that you are discharging any ___ before you begin working on that device.
capacitors
Your computer or your laptop uses DC power, direct current, to be able to operate. But the power that’s coming out of your wall outlet is alternating current, or AC. We use power supplies to convert 115 volts AC or 220 volts of AC, depending on where you live in the world, into something your computer can use. Most often, that’s __ volts of DC power, __ volts of DC power, and ___ volts of DC power.
3.3
5
12
What is the fundamental difference between alternating currents and direct currents?
Alternating current is constantly reversing direction as it flows through the electrical lines. This allows us to efficiently distribute AC power over very long distances.
The primary characteristic of direct current is that it’s moving in a single direction with a constant voltage. This is what is required by most electronics.
If you connect a 220 volt power supply to a 115 volt power source, there is usually no permanent damage.
True or False?
True
If you connect a 115 volt power supply to a 220 volt power source, there is usually no permanent damage.
True or False?
False
Can destroy power supply and computer components.
~
AC
DC
What do switches on power supplies do?
Match input voltage (100v-220v) to the needed voltage. Some power supplies can automatically switch.
What can you use to see what kind of power supply you may need for an unknown outlet?
A multimeter. It can measure the voltage of the outlet.
You can connect a 24 pin connector to a 20 pin motherboard.
True or False?
True
What are some components that would use 12v?
fans, PCIe adapters, hard drive motors
What are some components that would use 5v?
some motherboard components
What are some components that would use 3.3v?
M.2 slots, RAM, some motherboard components
What computer component tends to use the most power?
Graphics card/video card
What is one reason to have a power supply above capacity?
Scalability; more power in case extra components are added later.
