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Power Supply, what is it?

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by louisa

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Okay, that is a dumb question, but up to now I figured my Power Supply was the actual 2-part plug that goes into the wall. Is that right? Or is the Power Supply something inside the computer that regulates power to the motherboard? When I type in Power Supply on google, it shows me power cords for the computers. Then when I read forums, it sounds like it's inside the computer.

Here is the problem: My HP ZV6000 keeps turning off randomly after 5-10 minutes of running. I hear a fan going on and off frequently. Doesn't seem to be hot. I thought it was a bad battery, bought a new one, charged it up, battery at 100% and also still plugged into the wall and it still will shut down.

It restarts, though. Then does the same thing.

I'm about to try it not plugged into the wall and I am sure it will do the same thing.

Just turns off, goes dead. Then I resatart it and it does it all over.

Is this a bad power supply inside the computer? If so, how do I check it? And where do I buy one?

The fan is going on and off frequently, could it be a malfunctioning fan?

Could it be the motherboard?

The computer is just 2 years old and unfortunately I thought was still under warranty for another year but the warranty ended 2 weeks ago (purchased $250 2 year warranty from CompUSA, found out it meant not additional 2 years from original manufacturer's, but it meant from date of purchase-overlapping with manufacturer's warranty the first year and only an additional year after that).

It's been doing this since August and was too busy to deal with it until now. Shucks! I blew it on the warranty deal what a waste of $250 bucks.

Anyone have any suggestions? I am no "techy" but a quick learner so please don't judge me on the very naive 1st question on the first line.

And if you say I should just buy a new one because repairing is costly, what is a good notebook. I hear lots of them don't run well on Vistas and that's just about all that's out there. Mac's too costly, program-wise.

17 replies

by tintoman

The bit you plug into the wall is the a/c adaptor, that converts a/c electricity into DC and lowers the voltage so that your computer battery can be charged and the computer will run whether or not you have a battery fitted in most cases.
Also there is a voltage regulator device inside the computer which does exactly what it says on the tin.
The shut down problem you describe could be caused by a dead battery, for example my own laptop will not run more than a few seconds on battery power because the battery is dead and cannot hold a charge.
Also your problem can be caused by overheating, if the airways are blocked by dust, the processor gets hot and the machine shuts down to protect itself from damage.
This is the more likely in your case because the machine still shuts down when on mains power.
You really need to get it checked and cleaned by a competent person.

by louisa

I had put a new fully charged battery and also had it plugged into the wall when it happened last.

So I probably need to get it cleaned and the only problem is there's no professional that can do it in time...how do I clean it myself? I've used the Dust Off.

by oh smeg

A Power Supply in the conventional Term is a Switch Mode unit that produces a stable low voltage DC Current of around 5 V DC and 12 V DC.

A Note Book as such doesn't have a Power Supply it has a Mains Adaptor and a Battery. The Mains Adaptor plugs into the Wall and produces what should be a Stable single voltage of around 20 V or less depending on the make & model of the NB involved.

Now your current problem is most likely a Over Heating Issue where the units BIOS is set to turn off the unit when the CPU reaches a certain Temperature. This is to prevent the unit from overheating and burning out. So that's a good idea. What you need to check is that any Air Intakes are not blocked some NB have the Air Intake for the CPU under the unit and if these are placed on a desk, table with a loose cover the cover can get sucked up and block the Intake allowing the CPU to overheat. This mostly happens when you hear a FAN running as that Fan should be the unit cooling the CPU & its Heat Sink to acceptable Levels stopping it from overheating.

What can also happen is that the unit can suck in dust and block the air passages partly or completely preventing the unit from working properly and keeping the CPU within the working temp range.

If it's the first you need to sit the NB on something that prevents the cover getting sucked up and blocking the intake/s. There are numerous Cool Pads on the market available to do this and also some clever other items are used to achieve the same thing but without the fans that a Cool Pad have. A cake Rack is used by some people to prevent the Air Intakes becoming blocked. But in reality anything that allows a free space under a NB will work.

If the unit has been run in dusty conditions the Heat Sink on the CPU can get clogged and stop allowing a free flow of air over it to cool the CPU. When this happens you need to have the unit cleaned by a professional.

Personally I always supply Cool Pads with any NB as they are USB Powered Devices that suck air under a NB and help to prevent dust getting sucked in as the dust tends to go with the faster flowing air and away from the NB into the Cool Pad. This removes the need to constantly have the NB cleaned.

Personally I use this Cool Pad but there are many others available and most of the time it's a personal choice what you use.

http://tinyurl.com/ny8zn

Col

by louisa

Great information about cleaning it. I never run it in the carrying case. I always run it on a nice flat table top. I've felt it run hotter when it wasn't broken so I wasn't sure if the heat was the problem.

I'm testing it again now. I used Dust Off to clean in the 2 fan vents and air intakes. I restarted it wihtout using the wall plug, running only on battery. (It's a new battery now).

It is started and running now for a few minutes. Takes 2 minutes for the computer to turn on.

2 error messages popped up:
"Microsoft Visual C++ Debug Library
Debug Assertion Failed!
Program: c\hp\drivers\hplsbwatcher\lsburnwatcher.exe
File: c\programfiles\microsoft visual studio.net 2003\vc7\atlmfc\include\atlfile.h
Line: 188
Expression: m_h!=0
Please retry the assertion"

Which I clicked try assertion again.

Then Lightscribe Burn Watcher has encountered a problem and needs to close. Send error message? Which I reported the error.

So far has been running for 7 mminutes with out turning off.

If it does turn off, I will try to immediately restart it, and if it won't does that mean it is overheated?

If it IS able to be restarted immediately after the shutdown does that mean it's not overheating?

Could it be a virus? I have Norton's on it.

If it were the motherboard would it even start at all? I've read that computers shutting down for no reason may have bad motherboards.

The problem is I can't get a professional to even look at it for a week, and I am in desparate need of my laptop for traveling in 3 days.....

I may buy a new one if I can't figure it out. How long do Notebooks last before having to buy a new one?

by louisa

Hey! I used Dust Off on the fans and the vents, and now my computer seems to be running okay! I still got a the error message about windows debugging C++ and lightscribe failure, BUT IT HASN'T SHUT OFF yet. It's even done automatic updates and restarted fine also.
It's a micacle!
I used to be able to leave my laptop on for a long time, sometimes days, plugged in of course. Now I don't depend on my laptop, only during travel, so is it possible that it was messing up due to lack of activity between July and August, just froze up from lack of use?
The last time it worked fine was in June in Tahiti where it was hooked up AC powered into a european adapter.
Then got back home and didn't use it until August when it was shutting down. I had tried it about 5 times a day for about a week and when it kept shutting down I put it away and was too busy to deal with it.
So now with the Dust Off, not sure if that's what did it or what...
Fingers crossed, knock on wood, maybe the problem has resolved...

by tig2

Don't forget to mark Oh Smeg helpful. It sounds as though your problem is solved.

Notebook computers are notorious for heat problems. I solve that by elevating the laptop about a half inch from the hard surface I am using it on. I use an inexpensive cooling rack (available at Target) to do this. Because the surface is wire mesh, it allows the free flow of air to the vents.

You can also use an Ice Pad. They force cool air to the vents. Targus makes them. While a good option, I spent less than $5 for my cooling racks rather than the $30 or so that an Ice Pad will run.

Just a thought!

by louisa

I did an experiment today:
#1) I used Dust Off on the fan area and the heat output areas (not disassembling it at all).
#2) Using my brand new fully charged battery, without plugging the power cord in to the notebook, I started it up, and it stayed on! Asside from a few error messages, it seemed to be working. It restarted a few times due to automatic updates, then appeared to run normally for over an hour. #3) The battery started getting low so I plugged the power cord in, and the monitor got dimmer, but it stayed on.
#4) I shut it down and then restarted it with the power cord still plugged in.
#5) Then the problem started all over again, shutting down within minutes of starting up.

When my notebook worked in the past, when I started the notebook with the ac plug in it alreay, the montior was nice and bright.
However, when I am running it on battery THEN plug in the power without shutting down, the monitor gets dimmer. Is this normal?

I am thinking that the power cord is no good and that's why it shuts down only when it is plugged in even when the battery is on full charge. I think when it is plugged in that it by-passes the battery and the power cord is the issue.

Could this be it?

The power cord is a little bent at the base where it plugs into the notebook, and wires are exposed at the bend. Maybe it's no good?

I worry because the more I attempt to start it and it keeps shutting down it could destroy the hard drive.

I don't think it's overheating because it starts up again right after.

by tig2

Often you can find one with a power cord like you have. Borrow a power cord, see what happens. If no error, use that shop to order the cord. They do go bad.

I put a bit of heavy tape where the cord is most likely to flex... and break. The tape will reduce the amount that the cord is able to flex. While it admittedly just transfers the problem elsewhere, seeing the tape is a visual clue to not bend up the cord too much.

I have a velcro strap that allows me to wrap the cord in a loose circle and secure it. This puts much less stress on the wires.

by oh smeg

If possible I would get it replaced ASAP but in reality you only have Monday with Tuesday being New Years you may not be able to get a new Mains Adaptor for this unit in time.

With these Mains Adaptors it's always a good idea not to stretch the Wires or attempt to pull them as that will cause the premature Failure of the Adaptor and maybe even the destruction of the NB itself as the Plug where you insert the Mains Adaptor can break which generally means fitting a New M'Board most people buy a new unit as the cost of repairs is prohibitive.
As for how long a NB will last this all depends on how it is treated. I have one here that I use daily that is over 4 years old and performs faultlessly but by the same token I had one of the same units only last a few weeks but I don't expect one that has been run over by a Big Excavator to continue to work either. :D

One of these units the same model that I sold to a customer and is younger than mine will be replaced this year after replacing the Battery in September last year but that is because it was never taken off mains power and when he carries it around now he failed to unplug a USB Lead for the Cool Pad and broke the USB Socket. Pity really as it's a nice unit that if treated properly would be around for a long time to come.

AS far as Mains Adaptors are concerned I would suggest unplugging it when the NB is not in use as they do get hot and this shortens the life of the unit and may even destroy the NB if the Adaptor goes Open Circuit. While not common I've seen a couple of Mains Adaptors send full mains power through to the NB and it's a spectacular failure to say the least. While I've never seen this happen judging by the descriptions that I've been given the Owner/User never wants to see it happen again either. So only plug in when you are using the NB and always unplug when not in use.

Col

by thechas

While the other answers have given an overview of a power supply, I will elaborate.

In general terms, a power supply is any device that converts one form of power into another. The most common consumer power supplies convert AC line power into low voltage DC power.

A simple power supply consists of a transformer (to isolate and lower the AC line voltage) a rectifier (converts AC voltage from sine wave to half wave) and a capacitor (stores energy from the half waves and smooths out the peaks to produce DC).

There are a large number of different power supplies, DC to DC converters, DC to AC converters, (also referred to as Inverters) and a host of others.

The supply I described above is a simple linear supply. Most computers use switch mode power supplies for the higher efficiency and lower weight for a given power output.

For your notebook, the primary power supply is the big block between the wall plug and the power plug on the notebook. There are some laptops (older Compaqs) where the AC line cord plugs directly into the computer.

Inside the notebook there are several power supply circuits. Most are regulator circuits that convert the battery voltage to the various voltages the different circuits need.

On a desktop computer, the power supply is the box that the AC line cord plugs into and has at least 3 sets of cables that plug into the motherboard and drives inside the computer. This is a switch mode supply.

As to your specific problem, I suspect you have a bad CPU cooling fan. Even a notebook won't run long without the CPU cooling fan.

As far as fixing it yourself, notebooks are a pain to take apart and put back together. If, you can get HP to sell you the fan.

I recommend that you ask around and find a respected local repair shop that works on notebooks and let them take a look at yours.

As to new, you can still buy some Dell and HP models with XP rather than Vista.
Another option, is Buy XG.
http://www.buyxg.com/category/ntbk/default.asp
You can configure their notebooks much more than you can a Dell or HP and even get it with no OS installed.

Chas

by louisa

Hey there,
I will do the cooling rack thing, my next experiment.

But I do you think my power cord is bad because I got the system to work on a fully charged battery for over an hour, no unintentional shutdowns....
Then when the battery was about 20% I plugged in the power cord, my monitor got dimmer. Then I shut down and restarted with the power cord in, and it started and shut down within seconds, did this 3 times. Finally an error message in DOS appeared on a large black screen. It would start again for a few seconds.

Next I will try again with battery charged with no plug in it.

Then if that works, I will shut it down and see if it will stay on with the power cord plugged in.

Have you ever heard of a bad power cord doing this?

by louisa

Hey Col,
Thanks for the feedback, and I am thrilled that this could be the only problem (so far), the broken mains adapter.

I have been successfully able to charge the NB while it is OFF. But my NB will not run with it plugged in at all. So, basically I charge it while turned off. Unplug it. Turn it on and run on battery for about 1.5 hours. Turn it off before it runs down...do it all over again. IS THAT SAFE TO DO IF IT IS TURNED OFF? Seems to be the only way I can get it to work.

I ordered an AC adapter plug at wholesalelaptopbattery.com
"LAPTOP AC ADAPTER FOR HP PAVILION ZV6000 18.5V 4.9A MULTI PIN (ACWLBA124) = $34.00"
Which is a great price (other sites being over $100), and looks like it will work with my model. Unfortunately it won't get to me before my travels, so I will have to make do with the constant recharging.

The wholesalelaptopbattery.com has great prices, just in case you haven't checked them out.

Mahalo,
Louisa

by oh smeg

Also as I'm involved in the industry I never pay retail for anything work related I always buy it at Trade. Well most of the time anyway just depends on the circumstances at the time but if I pay retail it's only small stuff.

Now back to your problem Using the Mains Adaptor to Charge the Battery may work but I really wouldn't recommend it as I'm not sure what Power it is putting out. If the Voltage has gone High it may damage the M'Board effectively destroying the NB in the process.

The most likely thing is that the Mains Adaptor isn't supplying enough Amperage to run the NB but enough to charge the Battery though it may take longer to charge. If that is the case there shouldn't be any problems with using the Adaptor to Charge the Battery but it could fail completely and leave you high and dry with no access to a computer while you are away. If the trip is important it may be worthwhile buying a new NB but if you do you need to remember that most have Vista loaded and most of the existing software made for XP will not run properly if at all on Vista. [i]May be important if you need to transfer any software between the 2 NB's.[/i] Of course if you look at getting a NB loaded with XP there is no problem but you should make sure that it is fully updated before you leave.

But no matter whatever happens the HDD is unlikely to be damaged from the Mains Adaptor at this point in time so any data on the drive should be easy to recover in case of a Worst Case Scenario occurring. That is if this is [b]Important[/b] to you of course.

Hope you enjoy your trip

Cheers

Col

by louisa

Thanks for the advise on the Mains Adapter.

Since I leave tomorrow, my choices are slim: either deal with this NB, get lucky and find someone in town that has the adapter, or get a new NB.

My last effort will be to visit Cicuit City to see if they possibly have the adapter, fingers crossed. If not, then I will decide if I buy a new NB just for the trip, which is rather expensive.

I suspect the adapter is giving off too little voltage because: even before the unintentional shut-down problem started happening in August, whenever I would have my NB running on battery then just plug in the adapter to save the battery, the SCREEN DIMS and stays dim noticeably. It still does this, only now it shuts off when plugged in after the monitor dims.

If the monitor dims when plugged in does that mean too little or too much energy?

It seems to charge at a reasonable rate. The green light on the Mains Adapter turns green when plugged in, and stays lit for 20 seconds after unplugging it from the wall and computer.

The blue "lightning bolt" charging indicator seems to go off after the charge is complete. That's normal right? When I unplug it then turn the computer on battery power after a fresh charge, it seems to start off at 98% or 95% instead of 100%. I figure the startup drains a bit.

Thanks again for your help, and hopefully others that have a shutdown problem like I did will test their Mains Adapter after reading this.

by thechas

Being that your AC adapter is described as a multi-pin and has a connector that looks like it has at least 4 circuits, I would suspect that there are different power supplies that connect to the laptop.

My guess is that 1 or more of the wires for the main laptop power have broken inside the cable. The wire for charging the battery must not be broken.

As Colin stated, you are running at risk. Both for having the adapter fail totally, or for damage to the NB.

Another thing to consider is that the failure may not be in the AC adapter itself, but with the power jack on the NB. With the more common round plug used on many laptops, the failure of the DC jack is total. With the multi-pin arrangement, it is possible that 1 or 2 solder fillets have fractured and that is why you can charge the battery but not run off of the adapter.

If the new adapter does not fix the problem, then it most likely is a problem with the power jack.

As to your trip, have you considered renting a laptop?

Might be worth it.

Chas

by oh smeg

[i]If the monitor dims when plugged in does that mean too little or too much energy[/i]

Generally this would be a Low Voltage but as you have wires exposed at the plug or at least near it it could be one of several things none of which are good. The most likely thing is that wires from different leads are shorting out. Not good for the Mains Adaptor and depending on what is touching what it may not be good for the NB either.

[i]The blue "lightning bolt" charging indicator seems to go off after the charge is complete. That's normal right?[/i]

Yes that seems about right to me but it all depends on how the NB was setup originally. Sometimes people like me keep the Battery Condition on all the time so it's easily accessed when needed.

[i]When I unplug it then turn the computer on battery power after a fresh charge, it seems to start off at 98% or 95% instead of 100%. I figure the startup drains a bit.[/i]

Here the battery probably isn't charging fully but at 90% + things are not overly bad you will just miss a bit of running time. While potentially a Nuisance not a big deal.

Th problem here is that you don't have a [i][u]Normal[/i][/u] NB Adaptor they mostly only have 2 wires going from the Adaptor to th NB so it either works or it doesn't. With your setup the Adaptor is doing a lot of the Voltage Conversion that would normally be done on the M'Board by the electronics. This type of setup makes a slightly cheaper NB but also far less reliable in most cases. But if you already know about this you can look after it differently and have as good a service life out of the unit.

As for what the Adaptor is actually doing it's anyone guess as it could be Low Voltage or Low Current. But as there are no motors involved here except for the HDD the likely hood of a problem arising is remote.

If you take this NB with you just remember to treat the Plug on the Adaptor where it connects to the NB very carefully.

Hope everything goes well on the trip

Col

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