Questions tagged [power]
Electrical power is essential to the operation of any computer and any of its components or peripherals.
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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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When do I need a pure sine wave UPS?
I would like to buy a rack UPS that would support all the IT related electronics in a SOHO room. This include switches, routers, PCs, servers, NAS. During my research I found out that there are ...
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How do I stop Windows 10 going to sleep after locking with Win+L key
I've got a Dell XPS 13 (9360) with Windows 10 Home.
Steps to reproduce:
Open power options (Win-X, O)
Click change plan settings next to the current plan ("Dell" in my case)
Set both "on battery" ...
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Does a computer use more electricity when charging USB devices?
Something I've always wondered. If I constantly hook up cellphones, hard drives and the like via USB to my computer, will it eat up more on the electricity bill? Or are the USB ports using up ...
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"Turn off router for 10 seconds" - Quantifiable? [duplicate]
Is there any quantifiable evidence to support power cycling routers for 10 seconds or any arbitrary amount of time, instead of just unplugging and plugging back in?
This is related to troubleshooting ...
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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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Are all power cords made equal?
Referring to this type of power cords that either attach directly to the PSU, or to a power adapter that powers the monitor or laptop.
Is there anything to watch out for when swapping these cords, ...
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Is it safe to power on a motherboard outside of its case?
I have a new motherboard which needs a BIOS update to support a new CPU.
Thankfully I have an old (compatible) CPU handy. My plan is to install the old CPU, update the BIOS, then install the new CPU....
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How much power does a hard drive use?
This is not as straight forward as it sounds.
Specs from Western Digital's site for a WD 3TB Green Drive:
Read/Write 6.00 Watts
Idle 5.50 Watts
Looks fine right? Look at this part of the spec:
"12 ...
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Can a power failure or forceful shutdown damage hardware?
Can computer hardware suffer damage from forceful shutdowns (holding the power button for five (5) seconds) or power failures?
I believe that normal PC hardware does not suffer from this - after all,...
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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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Where does power consumption go in a computer?
Today we had a weird discussion over lunch: What exactly causes power consumption in a computer, particularly in the CPU? (ETA: For obvious reasons I don't need an explanation why a hard drive, ...
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180W Laptop charged with 45W charger, is it dead?
My brother gave me a dead gaming laptop (Asus GL503V). He bought it on eBay some time ago but it died a couple of months after. A couple of days ago he gave it to me, and I noticed that the charger ...
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How can I force an internal hard drive to power on or off when I want?
Obviously there are power management settings which Windows uses to determine when to power a hard drive off, and when to power it back on again. Powered down I assume doesn't mean absolute zero power,...
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Removing the CPU while the power is on [closed]
What will happen if I remove the CPU while the power is on?
Does anything happen to the computer?
Has anyone tried this?
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Is it bad to leave your computer on during a thunderstorm?
Generally when I hear the crack of thunder, my PC goes off immediately. Today I'm working though, and wondered - how bad is it to leave it on? If the power goes out, will it kill it?
I use a power ...
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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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Does installing larger RAM means consuming more energy?
Since every bit of a dynamic memory module needs to be refreshed to keep it's data, does that mean that if I install a module with more capacity than the current one on my laptop, more energy will be ...
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Power consumption: SSD vs HDD
In questions like this one and in websites everywhere it's noted that SSDs use much less power than HDDs... usually citing ~2 W vs ~6 W for HDDs, my question (and sorry if its stupid just need to be ...
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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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The Flight I am taking has USB ports for power... how can I use it to charge my laptop? [duplicate]
Possible Duplicate:
Charge a laptop via USB power (500mA)?
I will fly to China in the next month which will take a mammoth 18 hour flight. The plane has USB power source on it.
I know USB only ...
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Does a power supply draw only as much power as it needs?
I recently built a small mini-itx Intel ATOM-based Ubuntu home server. The case I choose is a small case but only a full size ATX power supply would fit it. I choose a mid-grade OCZ 500 watt modular ...
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Laptop sometimes shuts down when out of power causing me to lose my unsaved files
Why does it do this? Most of the time my laptop just goes to sleep when it gets to 0% power. But sometimes it completely shuts down and I lose my unsaved files.
Is this a problem with my laptop? The ...
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How much electricity is there in the "power switch" button cables?
Because of a broken power button on the front of my computer I've had to take the cables connected to the button and create a sort of "hotwire" setup to start my computer. This is done by simply ...
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USB Type C Power Delivery Profile - max length?
The new USB-C connector allows for 100W to be delivered to charge laptops etc.
Is there a maximum length for a charging only cable?
The specification talks about cables being less than two meters ...
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Is there a USB wall charger that "just works" with every device?
Background
Almost every gadget today is charged over USB. It seems like a good idea since everyone has a computer with USB, but fumbling behind a computer and making sure that computer is on and does ...
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Detecting when a server is running on UPS battery
I have a home server (HP Proliant ML310 G4) that I bought from my employer a month or so ago. The server runs Debian Linux and I use it for just about everything. I can get away with doing this ...
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Is surge protection actually needed?
Am I am an idiot for not using a surge protected powerboard?
Does this mean my computer gets fried in a power outage? Which particular parts of the computer are most vulnerable to damage if I get a '...
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Is a UPS a good investment for a home machine?
Is it worth the money to invest in a battery-backed UPS unit for a home machine? Or is it a waste of money? The purpose of the UPS would be to prevent a "meltdown" of the computer due to bad power ...
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What do you do when you're not allowed to turn off the computer (but must)?
We've all been there. You're installing a new major system for a client and you're finishing up with installing all required updates and this happens.
Image taken from petur.eu
Or, more specifically,...
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Prevent Windows 7 PC from sleeping while a download is in progress
While I'm downloading a large file on Windows 7 using Google Chrome, my computer goes to sleep. I could obviously set the computer to not sleep at all (or change the interval before the computer ...
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Why does pulling the power cord then pressing the power button fix a non-booting PC?
I've been working at this institution for about 6 years. One thing thing that I've always found curious is that sometimes—especially after a power outage—we find a PC that won't boot when the power ...
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Will stopping hard disk when inactive also stop downloads?
If I enable to turn off hard disk when inactive in Windows Power Plan - Advanced Settings, will it also stop my downloads in different programs? Currently my Internet connection is slow.
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Can I safely charge my laptop with a non-standard, third-party charger? [duplicate]
I have a Toshiba Satellite laptop. My charger has stopped working.
I have access to a Lenovo charger. Can I use this charger on my laptop?
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How to turn on computer via USB Keyboard [closed]
I have an interesting query, my cat can turn on my computer by walking/laying on my keyboard when it is powered off, but I cannot find a way to do this intentionally.
I have tried to google it, but I ...
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What is the 6-pin power connector on an HP ProDesk?
I have an HP ProDesk 600 G1 desktop PC, and I'm upgrading it with a new graphics card and a new power supply.
Now, the problem I'm having is that the motherboard in the PC doesn't have a standard 24-...
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Detecting unauthorized USB devices by power draw
How can I measure the power draw for USB devices connected to my computer?
For instance, if I wanted to detected an unauthorized or malicious USB device such as a keylogger, is there a way I can ...
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How to check if my eSATAp port provides 12V power?
I have a Lenovo ThinkPad Edge 13" model 0217-2QG with eSATAp port.
How do i check if my port provides 12V power (enough to power a 3.5" HDD)?
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How to "restart/repair" an USB port?
My laptop has two USB ports, but one is broken, so I use a USB hub in the other good USB port. In that USB hub, I use a mouse and keyboard. Suddenly, that USB port doesn't detect the mouse and the ...
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Are there any good reasons for halting system without cutting power?
Are there any good reasons to halt a system without switching off power to the hardware? I mean using the halt command without using the -p switch.
I haven’t been able to find an answer on the ...
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Do SSDs “turn on”?
Hard-drives have a definitive “on” status (they spin up, the heads move, and they use more electricity than when they are “off”). The same goes for a computer (fans and lights activate), monitors (...
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Can I safely connect the power-only-end of a USB-Y cable to an other power source?
If the host computer for an USB device doesn't provide enough power for a device which has no dedicated power port, can I connect the power-only-plug of a Y-USB-cable to an other computer, an USB-...
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ATX power: 20 or 24 pins?
What is the difference between 20-pins ATX power cables and 24-pins ATX power cables for motherboard? I see that Cooler Master Silent Pro PSU has an extensible plug, showing 20 pins + 4 pluggable pins....
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Is there a way to power down a USB device using software?
Is there a way that I can power off a (specific) USB device completely using software from a Linux machine?
I want to use this to power off (so that the LED is off) a (single) USB stick.
Do you know ...
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How much power the system is REALLY consuming?
I suspect that my ATX case's power unit from China provides FAR LESS power than it's supposed to. Is there a way to see (in real time) how much power the whole system is trying to consume and how much ...
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Buying A Computer "Case" Fan... Does It Always Run At 100% Unless Told Otherwise?
What happens if I do not plug it into the motherboard and it does not have a switch?
I have seen fans before with an "off/low/high" switch that allows you to manually set their speed.
I have seen ...
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How to force power-off of a Samsung Series 9 laptop?
No, the four-second hold on the power button isn't working.
The battery is built-in and not user removable.
I was working on installing Fedora 15 on a new Samsung 900X3A (a very neat machine) and ...
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How much power do video cards use after Windows turns your display off?
Modern video cards seem to use 150-200 Watts at idle. Does this mean that this is the minimum power the video card will ever draw while your computer is on? It's clear that if you are sitting at the ...
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What is the "known hardware incompatibility" that disables PCIe Active State Power Management? How do I fix it?
I'm on Windows 7. I just ran a Power Efficiency Diagnostics Report through powercfg -energy and I got this error:
Platform Power Management Capabilities:PCI Express Active-State Power Management (...
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Change what closing the lid does, from the commandline?
I wonder if anybody knows a utility, or command, which can change this setting in windows in one click. I often need to change it on my laptop whether I want it to do nothing when the lid is closed or ...
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