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

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35
votes
5answers
18k 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 ...
20
votes
3answers
58k views

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 ...
1
vote
1answer
3k views

Can you charge a tablet and use a USB device at the same time?

Most tablets only have a single Micro USB port that is used to charge the tablet, or can be used to plug in regular USB devices like a keyboard/mouse using USB OTG. I would like to charge/power my ...
3
votes
2answers
10k views

PC power supply & normal range for voltages reported in BIOS hardware monitor?

I'm trying to diagnose whether my computer has an ample power supply. Sometimes when I play a video-intensive game, both monitors lose the video signal, even though the computer remains on and sound ...
5
votes
2answers
4k views

Surface Pro 2 / Windows 8.1 - Charging Issue

I purchased the Surface Pro 2 a few days ago (release day) and it has been running great, but over the last 3 days I have encountered a weird charging issue. I like to drain my battery down to near ...
1
vote
1answer
23 views

Toshiba Laptop suddenly shuts down when on battery

I'd be grateful if someone coud help me. My Toshiba L845 laptop suddenly shuts down when on low battery. It doesn't hibernate in the usual way it did. It completly powers off, as if someone had pulled ...
-2
votes
0answers
20 views

Universal adapter - which one to use on Acer laptop [duplicate]

I have Acer 5733 and my old adapter didn´t work (specification: 19V, 65W, 3.42A, 5.5mm*1.7mm). So I bought Omega OZU70W Universal power adapter for my laptop. It worked nice, my batery is charging and ...
3
votes
3answers
2k views

Laptop battery charging stuck at 90%

My laptop battery charged week ago up to 100% (fully). Recently, I noticed (within this week) that it now charges only to 90%. First sign was that laptop battery led now always orange (charging) and ...
0
votes
3answers
4k views

Should my HP Pavilion dv6000 operate w/o battery pack while using electrical plug-in? Mine won't

While using my computer, it shut down, and I cannot get it to turn back on. I have tried removing the battery to see if the computer would work without it, but it did not. The light is on where the ...
1
vote
1answer
3k views

Laptop shuts off unexpectedly while in motion

Recently I've been encountering a very annoying problem during my commute in which my laptop unexpectedly powers off. I am using a Dell Inspiron 15 with a touchscreen. The laptop is just a bit over a ...
-1
votes
2answers
53 views

USB 3.0 port as 20v power supply [closed]

I'm looking for a way to get the stated 20V 5A out of an USB 3.0 port to power an amplifier. Found power supplies but no easy USB 3.0 cable to DC power jack/connector (20V). Does it exist either or ...
1
vote
2answers
34 views

How to ground a laptop which does not have an earth pin

I have a laptop which does not have an earth pin on its plug. Because of this whenever I try to record audio using an external microphone there is a terrible buzzing sound. How can I fix this problem ...
2
votes
2answers
33 views

How to measure a CPU overheating process when in Idle Mode?

Every time my PC is idle for an hour, I return to find the fan at maximum speed and the CPU at 51-52 degrees. It's Windows 7 on an 8150 octocore from AMD. The task manager shows that two of the cores ...
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 ...
4
votes
0answers
119 views

What happens during a hard reset?

What exactly happens when you hold down the power button and perform a hard reset? Does it involve only hardware, in the sense that it shuts down power and everything crashes in its current state? ...
0
votes
0answers
12 views

Toshiba Satellite L850 power adapter

My Toshiba Satellite L850 power adapter gets extremely hot when I am using my laptop. I have noticed recently it seems to be getting worse. I make a point of unplugging it from the mains in case it ...
19
votes
5answers
46k 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: ...
-1
votes
0answers
23 views

UPS battery rapid discharge when turned off (from the power button)

I notice twice now that when I turn off a UPS from the power button, its battery rapidly discharges. Today it discharged from 100% to 20% in about 30 minutes. The batteries themselves are fairly new, ...
2
votes
1answer
69 views

UPS doesn't work on off-grid solar power system

My APC 350 UPS worked fine when plugged into standard utility company power in the States. Now it's being powered by an off-grid solar power system in Central America, using 120 volt power from a ...
0
votes
0answers
28 views

Laptop charger voltage fluctuation

I had sent my laptop(Dell inspiron 5520) for repair as it wasn't getting charged at all. The battery was working fine though. The technicians at the service centre told me that the voltage ...
0
votes
0answers
29 views

Computer doesn't start unless case is opened

The power button just does nothing. The cord is fine, the outlet is fine, the power switch is on. Literally the only thing that fixes it is to: open the case pull the power supply out (without ...
1
vote
0answers
40 views

Windows 10 Professional: Doesn't Boot after Power Outage

I have a Windows 10 Pro tower (Lenovo ThinkServer 440) which has two SSD drives setup as Raid 1 (mirror). The computer is super fast and stable! Except when there is a power outage. And here is ...
0
votes
3answers
69 views

How does ethernet, coax, and telephone surge protection work?

So I'm planning on buying a UPS and I see that they have ports for protection of ethernet, coax, and telephone lines. I've read answers on these three questions, but none of them address this ...
1
vote
1answer
5k views

AC adapter burnt due to high voltage spike but is my computer damaged because of this?

There was a high voltage spike in our area. My laptop stopped working and the little bulb in the refrigerator stopped working as well as an air coniditioner. When I touched the laptop I felt a ...
0
votes
1answer
34 views

Lenovo laptop, Windows 10 not charging battery

I have a Lenovo G500s. It came with Windows 8.1 pre-installed with the battery working fine. I've installed Windows 10 on the laptop now and suddenly the battery is not recognized anymore. It says "0% ...
0
votes
1answer
25 views

Powered Laptop Automatically Starting Up (Unintended)

I recently had a hardware failure and replaced my hard drive with a new one. Then having done a fresh install of Windows 8.1 (which then was upgraded to Windows 10). I'm having the same issue ...
27
votes
12answers
81k 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 ...
1
vote
0answers
40 views

How can I repair a power supply for a Apple's Power Mac G4?

This is an attempt to gather a reference page for anyone trying to replace a failing PSU from a Power Mac G4 with an equivalent ATX in the future. There are still a couple of pages -luckily- ...
0
votes
1answer
3k views

Compaq Presario CQ71 no power - power LED lights up briefly when plugged in

I have a Compaq Presario CQ71 which will not power on. When plugging in the charger, the LED turns on for about 10 seconds, and then turns off, no other lights turn on. Nothing seems to be happening ...
0
votes
3answers
42 views

Can i split a microUSB to plug into the wall and computer

A USB has 2 power cables and 2 data ones afaik. If i were to split these and re solder them to make essentially a Y cable with one USB A for power and one for data, and then plug the power into wall ...
0
votes
0answers
37 views

auto power on after power loss after orderly shutdown

I configured my computer to auto power on after electricity power loss, through bios. But, I also want to auto power on my pc after electricity power loss after an orderly shutdown. for example if : ...
0
votes
0answers
141 views

Dell XPS 1330 / 1530 - Won't turn without power lead, but you can remove power lead once turned on?

As the subject states, I can't turn on my dell xps 1330 without the power lead in. There is nothing from pressing the button. It has a newish fully charged battery and have tried a couple of good ...
0
votes
0answers
448 views

DELL n5010 randomly powering off

I have a Dell N5010(Inspriton 15R) laptop. The laptop will run for a while (10 mins) then cut out, I at first thought this was a overheating issue. This issue still happens even the the BIOS I've ...
2
votes
2answers
4k views

Dell inspiron n5010 has failed to recognize AC adapter

Recently my dell inspiron n5010 has failed to recognize my 90W adapter (despite powering it just fine). Full error message: "The AC power adapter wattage and type cannot be determined. the ...
1
vote
2answers
407 views

USB devices prevent computer to turn on

I have a dell optiplex 960. If I plug in 3 usb devices (keyboard, mouse, printer) all to 3 usb ports next to each other (there is a row of 4 and a row of 3 on the back of the computer), It will not ...
1
vote
0answers
21 views

Lenovo Y50 SSD upgrade - powering on issues

I recently upgrade my laptop (Lenovo Y50) from a 1TB HDD to an equivalent 1TB SSD from Samsung. I used EaseUS ToDo copying tool. When the computer boots up, everything works BEAUTIFULLY! Better than I ...
0
votes
1answer
26 views

Can I schedule a task when I hit power button on windows 8.1 tablet

I want to run a application before my windows tablet go to sleep/hibernate mode when I hit power button. Actually it should be triggered before entering sleep/hibernate mode but I'm ok if hooks power ...
44
votes
14answers
19k views

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 ...
0
votes
1answer
32 views

Battery is shown as fully charged but does not feed the laptop

My laptop is a young Acer V11 Touch (V3-112P-P2E7). Yesterday I used it regularly on battery mode and I left it charging overnight. This morning's surprise is that the laptop only works when connected ...
0
votes
1answer
420 views

Why does my Samsung laptop computer think it is unplugged?

Samsung laptop, purchased new in 2012. Windows 7 64-bit. 8GB RAM. Model NP300V5A. I woke up one morning and woke the laptop. I had left it plugged in to the wall the night before. When it woke, it ...
-2
votes
1answer
53 views

Is it safe to plug in a computer to a surge protector or a outlet? [closed]

I noticed that my old psu connector cable blew up beacuse of unplugging it correctly like pulling the connector off it was just the rubber peelling off and other rubbers with metal inside with ...
1
vote
2answers
64 views

Force laptop to use battery, not charger

I was wondering if it was possible to force a laptop running Windows to use its battery as the power source even when a charger is plugged in? If so, is it possible to switch between power sources ...
0
votes
0answers
15 views

Turn off power to single USB port… Temporarily [duplicate]

I have a desktop running Windows 10. I have an led strip that is powered via USB. I would like to set this on a clock to turn on at a certain time and turn off at a certain time. Is it possible to ...
0
votes
1answer
32 views

Power supply or motherboard busted. How can I fix it quick?

A few days ago, my desktop PC just stopped turning on. Pressing the power switch elicits no response altogether. This is the sum total of the troubleshooting steps I've done: Super-newbily switched ...
2
votes
3answers
24k views

How much power does a Western Digital Passport Essential SE require?

I have looked at the Western Digital website for my product (WDBACX0010BBK) and cannot find how much power the device requires. The device is not recognized when I plug it into my keyboard's USB hub. ...
0
votes
2answers
891 views

ThinkPad X220i appears to power on but won't start - no BIOS or beeps

I have a ThinkPad X220i laptop here (4-5 years old, out of warranty) that won't power on any more. Looking for any tips to get to the cause and repair it. The problem: When you press the power button ...
1
vote
1answer
27 views

Rename power plans in Windows 7?

Is there a reliable way to rename power plans in Windows 7? Creating new ones with a new names is not too hard, but some systems have dozens of power settings (including advanced settings) in each ...
0
votes
1answer
51 views

UPS suddenly restarting, what might be the cause?

Background My UPS has a backup of about 10 mins, thus, it's battery life is good. No problems detectable. My CPU, on the other hand, is also fine with no major hardware problems (as it looks so) ...
0
votes
1answer
28 views

Did not unplug computer, power outage. Is it safe?

My office building is doing some maintenance work and they said they will shut off the power supply from midnight to 6am -- They told everyone in the building to turn off their computers and unplug ...
1
vote
3answers
2k views

Disconnecting a USB device without unplugging it

I'm modifying my desktop computer case and I want to plug everything into the USB ports in the back of it. However, the ports are not easy to reach and sometimes I have to unplug some devices because ...