Questions tagged [power-supply]
A power supply is an electronic device that supplies electric power to another device, such as a computer, monitor or printer. This is achieved by converting wall power (or mains power) to a lower voltage, and in most cases also from AC to DC. Most power supplies also provide protection from overload, power surges and other potentially problematic or hazardous conditions.
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Should laptops remain plugged in when their battery is 100% charged?
When your laptop's battery is 100% charged, should you leave it plugged in so any battery power doesn't get used, or will that cause overcharging, overheating, etc.? Should the laptop be unplugged ...
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What is the power output of a USB port?
As the title says, what's the power output of a USB port?
Is it a standard value, or it may change depending on manufacturer/model, and so on?
If that value is not standard, how can one determine ...
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Why do some AC adapters and power supplies generate a whining noise, and what can I do about it?
I have many different AC adapters and power supplies for a variety of devices, ranging from small 5V/1A USB chargers to laptop power adapters and desktop PSUs. However, I often hear a whining noise ...
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Why are my games slower on battery power, even with the power plan set to High Performance?
My laptop is capable of running most games on high settings at decent frame rates. However, if the power cable gets unplugged while I'm playing, the game immediately starts slowing down, even if I'm ...
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What happens when hardware tries to draw more power than power supply can provide?
As far as I understand, computers don't always draw the same amount of power from the power supply all the time. There are times when hard drives are on standby and not using as much as when they're ...
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Laptop power supplies, does current matter?
I have two laptops (same manufacture), with the same type of power connector.
However, the power supplies/transformers are slightly different.
The output on the first laptop's power supply is 15.6&...
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How do you check how much power a USB port can deliver?
Some laptops have a special USB port that can deliver more power than the other ones. However it is not always easy to identify which one is the good one, nor how much power it can deliver.
So is ...
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Pulling the plug out for 10 seconds
When calling support the other day he told me to reset my DSL modem by pulling out the power, leave it out for 10 seconds, and then plug it back in. This is something I have heard many times with ...
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How to choose a UPS / calculate power for a new PC
Seven years ago a friend gave me a Liebert PowerSure 250 UPS and it has done well for whatever (home) PC and monitor I've plugged into it over the years. I've just ordered a new PC with the Intel core ...
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Why are there so many pins on a SATA power connector?
I was just looking at the power connector for a SATA optical drive and noticed that it had fifteen pins!
I then marveled at the data connector next to it, which has a measly seven pins.
I know that ...
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I plugged in a molex cable the wrong way and the power supply exploded. Did it kill my hard drive?
I bought a cheap kit allowing me to use a 3.5 SATA hard drive with a laptop, by plugging it in with USB. It still requires external power supply so I used an adapter that came with this kit but I ...
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Can touching any hardware inside a running PC be dangerous for you?
I'm curious, if all the hardware gets power from the PSU's DC power lines, which provide a max. voltage of 12V, can you get electrocuted by touching some of the hardware?
user81496
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Why are brownouts so harmful?
I was reading Is surge protection actually needed? and well I'd like to know why brownouts are so harmful. The explanation gave there is "the capacitors get above their rated voltage" But that makes ...
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Do DC adapters consume energy when no device is drawing DC current?
Do DC adapters consume energy when no device is drawing DC current?
Or… Can I leave my mobile (5-20 W) or laptop (40-60 W) chargers plugged in and switched on and hope they won’t draw current if my ...
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Computer is frying all USB devices that are connected
My computer specs are as follows. The computer is almost 1 year old. It is custom built:
Motherboard: ASUS h510m-a
OS: Windows 11
PSU: EVGA 500BR
In the past hour, I have connected multiple mice and ...
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