Electrical power is essential to the operation of any computer and any of its components or peripherals.

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15
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2answers
19k views

Can I safely charge my laptop with a non-standard, third-party charger?

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?
27
votes
12answers
83k views

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,...
6
votes
3answers
2k views

Can a 20V 4.51A power supply be used with a computer that requires a 19V 3.42A power supply? [duplicate]

I have a laptop that says it needs a 19V 3.42A power supply. I have a Dell 20V 4.51A power supply. Can I use this power supply with my laptop, or will it destroy the machine?
8
votes
2answers
2k views

Power Supply Capacity Formula

Given that I am building a home computer from scratch and I have several components (MB, CPU, HDD, Video, Sound, etc) which have specific power requirements, is there a formula for me to calculate the ...
20
votes
6answers
39k views

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 ...
33
votes
5answers
14k views

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 ...
21
votes
7answers
8k views

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 '...
11
votes
5answers
21k views

How can I calculate power consumption of my PC in Watt?

How can I calculate power consumption of my PC in Watts, to prove my House owner (I live on rent), my PC doesn't consume much power? He blames me for huge power bills even though he uses a Fridge, A.C....
19
votes
5answers
20k views

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 ...
11
votes
6answers
39k views

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-...
3
votes
3answers
9k views

Computer won't stay powered up

I have just tried to turn my PC on this morning and it won't stay powered up. It will come on as normal for about 5 seconds, not quite long enough for the monitor to wake up. Then it will power off. ...
6
votes
4answers
21k views

Does the wattage on a power supply simply mean the max output wattage?

If I have a system running at ~500W of power draw, will there be any tangible difference in the outlet wattage draw between a 1200W power supply vs, say, a a 800W power supply? Does the wattage only ...
12
votes
6answers
20k views

Is there a USB power consumption meter?

For example, how could I measure the normal power consumption of my USB keyboard? After I get my statistics, I may easily notice when a hardware keylogger gets installed, by the changed power ...
4
votes
2answers
7k views

Is it safe to carry laptop around in sleep mode?

I heard that a hard disk in a laptop is more susceptible to damage if it is turned on. A person damaged their laptop's hard drive by having their laptop on while it was in their backpack. I also ...
12
votes
7answers
26k views

Can I charge USB devices from a powered hub that isn't connected to a PC?

This will probably sound familiar to most of you... In my home, we have a whole bunch of devices that can be charged via USB (two iPhones, a BlackBerry, an iPod Touch, etc ad nauseam). We also have a ...
12
votes
1answer
14k views

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)?
10
votes
4answers
45k views

Delay the screen lock in Windows 8.1 until some time after the screen turns off

In Windows 8.0 there was an option in "Change PC settings" (the metro-style modern mode settings) to lock the screen after the screen has been off a certain amount of time. If you turn the screen on ...
5
votes
4answers
15k views

Can I use a charger with less Ampere than the original?

I have a Sony Vaio PCG 61212W laptop. Because I got it from India, I needed a Uk power cord. I therefore ordered a power cord which is 3A and 250 volts. But the one I have with me currently reads 2....
11
votes
10answers
29k views

Disable or sleep secondary hard drive in Macbook

I've done some quick Googling but didn't find an answer. I've put an SSD in my Macbook, and at the same time moved the original hard drive to the optical drive bay. I'm running the OS and most of my ...
17
votes
3answers
13k views

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 ...
2
votes
4answers
2k views

Computer won't POST after power outage

I had just turned my computer on and windows was loading when the power in my neighborhood went out. Normally, when I turn my computer on, the video card fan spins up, then slows down, POST and ...
1
vote
1answer
3k views

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 ...
1
vote
3answers
10k views

PSU failing or Mainboard failing?

I am having some troubles lately powering on my desktop workstation. While starting up the PC after being off for hours (usually at least 8 hours) it randomly fails to do so. What happens is that : ...
5
votes
3answers
106k views

Is the 4-pin PSU connector required? (Trying to connect a PSU to a mini case.)

I am trying to build a computer, placing an ASUS P8H67-I DELUXE in a custom retro C64 case. The case is an extra small form factor which can accomodate the Mini ITX board, but requires an external ...
39
votes
3answers
277k views

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 ...
4
votes
1answer
7k views

Sleep shortcut in win7 [duplicate]

Possible Duplicate: What is the command to use to put your computer to sleep (not hibernate)? When I try to create a sleep shortcut in windows 7 x64 using this code: C:\Windows\System32\...
19
votes
5answers
48k views

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: "...
15
votes
6answers
27k views

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 ...
19
votes
8answers
842 views

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 ...
15
votes
3answers
3k views

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 ...
14
votes
4answers
21k views

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 ...
8
votes
3answers
1k views

Best Way to Protect A Desktop From Power Surge/Dirty Power?

What is the best way to protect a computer desktop from a power surge/dirty power? Would a power strip be adequate? (I don't have much space in my desk.)
2
votes
3answers
11k views

How to control power to USB ports using batch

How can I toggle the power to a USB port on/off using batch or the command line? I am using Windows 8 to do this. Does anyone know what I could do? I have 4 USB ports.
3
votes
4answers
4k views

Is there considerable energy saving using a black background on my website?

I had heard that you can save power by using a black background instead of a coloured background. Is there any evidence that this saves power on people's monitors? Is this a way that we can cut ...
15
votes
4answers
2k views

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 ...
4
votes
1answer
6k views

Is it safe to use a laptop AC adapter with 220V power if the AC cable is not rated for 220V?

The AC adapter supplied with my laptop is designed to accept voltage in the range of 100-240VAC at 50-60Hz, but the AC cable that plugs into the adapter unit itself is only rated to 125VAC 7.5A 2.5A. ...
4
votes
1answer
1k views

Electric shock with plugged in VGA cable [duplicate]

Possible Duplicate: Why would I get an electric shock from a VGA cable connected to an LCD monitor? Similar to this question I got shocked today with a new computer I just bought. How is this ...
3
votes
1answer
9k views

Desktop bios “After Power Failure” setting behavior

I know what the bios setting does but I have seen 2 different behaviors when this "After Power Failure" setting is set to "power on" Here are my main questions, does the bios know if the PC was ...
3
votes
0answers
383 views

Unplug computer during thunderstorms?

I once heard from a friend of mine that it's good practice to disconnect your computer and tv during a thunderstorm to avoid damage from electrical surges caused by lightning strikes. It kind of makes ...
3
votes
3answers
5k views

Is unplugging the power from a PC in standby or in normal mode bad for it?

Is unplugging the power from a PC in standby or in normal mode bad for it?
2
votes
1answer
336 views

Can as device that runs of USB be powered from a charger?

I have a Dreamgear PS3 Elite Gaming Headset that needs to be plugged into a USB port to power it, it cannot be used as just a "normal" set of headphones though it has a standard 3.5" plug as well (don'...
2
votes
2answers
460 views

Can I create/save a hybernation state to recover from *without* actually hibernating?

I'd like to be able to have my computer resume to it's last state (open programs etc) in the event of a forced or unintended power-off without having to actually hibernate or hybrid-sleep my machine. ...
12
votes
8answers
17k views

How can I use my computer to control my house?

I would like a way to use my computer to control the lights and appliances in my house. Does anyone have any good suggestions on how to do this. I would prefer to do this as unobtrusively as ...
35
votes
5answers
20k views

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 ...
10
votes
2answers
2k views

What happens when laptops reach 100% charge?

I have been reading alot of mixed views on how Lithium Ion batteries work when it comes to laptops. I have the new dell xps 15, with an intel i7 cpu, 16gb ram, and a 512gb ssd. Is it bad for the ...
33
votes
14answers
7k views

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?
20
votes
4answers
48k views

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,...
11
votes
4answers
9k views

What is dirty power?

What is dirty power? I recently saw a question regarding this, and I never really understood what this meant.
17
votes
6answers
12k views

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-...
7
votes
1answer
9k views

Windows XP/Vista/7 Check Battery Charge from CMD?

Does anyone know how to get the battery status in windows? On Linux it is as simple as acpi -b but in Windows this simple task seems impossible. powercfg -energy can get all kinds of all information, ...