Solved PSU burned out while computer was off & attached to UPS

Hewlett-packard Hp pavilion desktop pc p...
May 13, 2013 at 19:07:51
Specs: Windows 7, AMD A6-3650 (Liano) quad core / 8GB
I have a refurbished HP P7-1234 that bought just after Christmas. I had it plugged into a CyberPower-425VA SL-Series Battery Back-Up System-CPS425SL. I haven't used the computer more than 3 or 4 times since I got it, but everything was working just fine. Last week, while the computer was off, I heard the alarm on the CyberPower go off. I was working on one of my other computers at the time, which is attached to a different UPS which is plugged into a different room socket. I stopped what I was doing to check out the alarm. I tried to reset the alarm, but it would go off, so I unplugged it and then unplugged the P7-1234 from the backup device. Needless to say, I was (and am) baffled as to what happened. I tried plugging the computer into a different wall socket, but nothing happens. It won't boot up. It was pretty clear that the 300w PSU is fried. I didn't realize it at first, but I can smell a burnt smell coming from the side of the box. I'm not sure what to do at this point. I paid under $300 for the computer, so it doesn't seem practical to take it to a service shop where repairs would likely exceed what I paid for it.

I guess I am grasping at straws, by asking this question, but can anyone tell me what the odds are that whatever happened may have only damaged the PSU? My assumption is that whatever caused the PSU to fry may also have taken out the motherboard, the CPU and who knows what else. I've looked inside the box, and except for the smell from the PSU, I don't see any burn marks anywhere, but I don't have any way of knowing if anything else was actually damaged. If anyone has any experience with these things, I'd appreciate some input. I don't want to trash the computer all together, if there might have been a simple fix. On the other hand, if I am going to need a complete rebuild, that wouldn't make much sense either.


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✔ Best Answer
May 14, 2013 at 10:13:39
Thanks, OtheHill,

The PSU you suggested sounds like a good choice. If I did this right, there ought to be a link below to the specs on my computer, right from HP.

http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c03363664&prodSeriesId=5187022

This morning, I actually took a look at the PSU on the older HP PC I was going to borrow from and I don't think it is compatible. Right now, I'm leaning more towards just getting a new PSU and giving it a try. The price, after rebate, of the PSU you suggested is still cheaper than taking it to someone who might charge a lot more.

Pardon a dumb question, but I assume that PSU's all come with the same bundle of cables and connectors? If that is the case, I think I can work through the installation. Your idea of taking photos first is exactly what I would do. In fact, I think I would take a short video beforehand so that I could point out where the various connectors would go, then follow that during the install.

Thanks again!!



#1
May 13, 2013 at 19:59:51
It is possible that either the power supply just went bad, especially if it was a cheap one (factory one or installed at the refurb shop), or (much less likely) the UPS went and took the power supply with it. I lean towards the first and the alarm was in response to the short within the power supply.
As to whether the motherboard or other components were fried as well, the best way to check this is to swap in a known working power supply (spare or from a working computer) and see if it is working.
Another consideration is that you purchased this recently (December) and though it was a refurb, it may still be under some type of warranty. If it is under warranty, take or send it back for repair or replacement.

You have to be a little bit crazy to keep you from going insane.


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#2
May 13, 2013 at 20:31:18
Thanks for your reply. The computer did have a 90 day warranty, but that's already expired. Replacing a PSU is something I've never done, but I might give it a shot. I actually have another HP desktop that I am not using at all, and I'll bet the PSU is comparable to the one in the HP P7-1234. I was planning to give that computer to someone who could use it. With my lack of experience with PSU's, I'd probably end up with two computers that wouldn't work. Another thought I had was to simply buy a new PSU. They're not all that expensive. This brings to mind another question. Would it make sense to buy a PSU that is greater than 300w? I often hear people suggest this sort of thing when you replace a PSU, but something tells me that a PSU with more wattage might than the computer came with might not be a good idea. Any thoughts on that? (Thanks again for your reply!!)

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#3
May 14, 2013 at 03:47:18
Fitting a higher wattage PSU is a good idea and will not harm your computer at all. Factory-fitted PSUs are typically cheap and low powered, just enough wattage to supply the standard factory hardware configuration, and consequently it is running at maximum capacity all the time which shortens it's life.

Your computer will only take from the PSU the amount of wattage that is required for all the hardware in total, so it cannot do any harm to fit a more powerful one. It simply means it will not be working at full output all the time so it is less likely to burn itself out.
You will then have unused wattage available should you decide to upgrade the hardware in the future (eg fit an extra hard drive, a better graphics card etc).

Even if you will not be upgrading the hardware, it's better to have a more powerful PSU running at only 50% or 75% of it's capacity, rather than having a low-powered cheap PSU running at it's maximum capacity.


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Related Solutions

#4
May 14, 2013 at 09:02:20
Changing out a power supply is not difficult. Just pay attention to where you need to connect wiring. The various connectors are keyed so you can't really connect the wrong one. A photo would be helpful too.

Post your computer model for verification, or provide the information on the power supply.

I assume it is an ATX model. Below is a good replacement unit at a good price.

If you feel up to it, I recommend you try connecting the power supply from the other computer temporarily into the non working model.

You don't even need to install it into the case. If you just connect the wiring that goes to the motherboard and try to start it, you will know if you have additional damage.

http://www.newegg.com/Product/Produ...


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#5
May 14, 2013 at 10:00:30
Thanks, Phil,

That information is helpful!


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#6
May 14, 2013 at 10:13:39
✔ Best Answer
Thanks, OtheHill,

The PSU you suggested sounds like a good choice. If I did this right, there ought to be a link below to the specs on my computer, right from HP.

http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c03363664&prodSeriesId=5187022

This morning, I actually took a look at the PSU on the older HP PC I was going to borrow from and I don't think it is compatible. Right now, I'm leaning more towards just getting a new PSU and giving it a try. The price, after rebate, of the PSU you suggested is still cheaper than taking it to someone who might charge a lot more.

Pardon a dumb question, but I assume that PSU's all come with the same bundle of cables and connectors? If that is the case, I think I can work through the installation. Your idea of taking photos first is exactly what I would do. In fact, I think I would take a short video beforehand so that I could point out where the various connectors would go, then follow that during the install.

Thanks again!!


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#7
May 14, 2013 at 10:52:38
The HP specs for your model show you have a standard ATX case, which is good. There are many versions of the ATX standard that reflect the changes in hardware over the years. That said, the power supply I linked is compatible with your HP.

The cable bundles vary somewhat from model to model. usually the difference is in the number of connectors. Power supplies come as powerful as 1200W. That power supply will have more connectors because it is assumed you need more, or you wouldn't need a 1200W PSU.

You will find there may be surplus cables. Some connectors can be separated or combined to form a larger connector. For instance the main power connector on your motherboard is most likely a 24 pin connector. The linked power supply has a 20 pin + 4 pin that slip together to form the 24 pin. That is done to make that PSU more flexible when used in older 20 pin systems. Just tie up any surplus cabling to keep it out of the fans and the airstream.

I doubt you will have any problems but if you do, you know where to find us.

You do need to take precautions with electrostatic discharge. Computer components can be damaged by static charges on your body. Just touch the metal case before unplugging the computer and you should be fine.

One more word of warning. If you decide to clean inside the case, DO NOT use a vacuum cleaner. Static again. Best to use compressed air to blow out the dirt/dust. Office supply and computer shops sell canned compressed air for that use.

Newegg.com is a very reputable online store. You can print the rebate form off their site.

See the guide at the link below.

http://www.newegg.com/Product/Categ...


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#8
May 14, 2013 at 15:00:44
Thank you very much, OtheHill (as well as Phil and Fingers) for all of your help. I never expected to get this much useful information. I'll let you know how things turned out once I've received the PSU and installed it. Even if this doesn't fix the problem, it will be good experience and it will give me the answers I am looking for. Without trying a new PSU, I won't ever know if that was all that the computer needed to be repaired.

Thank you once again!!


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#9
May 14, 2013 at 17:05:18
Thank you for providing useful input and for responding back. Unfortunately many don't bother.

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#10
May 15, 2013 at 11:35:25
I've been working with computers since before Microsoft introduced Windows, and I've learned a great deal about how they work. My "expertise", if I may call it that, is more on the side of the use and function of programs geared towards publishing, graphics and prepress operations used in the printing field. Where I work, I am relied upon to be, among other things, the IT person. I manage to do this, not because I know everything, but rather because I can always find answers to computer related issues and problems online. This time around, the issue was with my own computer and I was fortunate to find this technical discussion site and received sound answers and assistance. I've tried similar sites in the past and found many of them to be more confusing than helpful. In my field, I am often asked for assistance by newbies who are attempting to navigate through higher-end programs like Quark, InDesign and Illustrator and I do my best to give good advice and assistance in a language that they can easily understand. It always makes me feel good when someone comes back and says "thanks for the help". I believe that it is important to recognize good people who go "above and beyond" what is expected to help others. You've added to my knowledge base and helped me to move closer to fixing the problem I have with my computer. Beyond that, you gave me the "tools" to fix the problem myself, whereas before, I doubt that I would have attempted it. I must say that this has been the best experience I've ever had with a technical discussion site. I can't thank you enough! In the future, I will certainly come back here whenever I need advice and assistance that I can count on.

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#11
May 18, 2013 at 18:39:57
Just wanted to tell you that I bought the PSU you suggested. It was modular, which is something I've never seen before. This morning I decided to install it. You were 100% correct. It was very easy to do. In fact, it was so easy that I didn't have to take photos or a video of the inside of the box before I started as I thought I would. I simply laid the new PSU on my desk and removed and replaced one cable at a time, until I was done. Then I removed the old PSU and installed the new one in its place. Before I buttoned it up, I hooked up a monitor, the keyboard and a mouse, plugged everything into my new CyberPower 1350AVR, flipped the switch on the PSU to on, then powered up the computer, and lo and behold, it booted right up perfectly. I took a few minutes to perform some system updates, then powered it off and buttoned up the side panel. Thank you very much (again) for all the help. I never would have attempted to replace the PSU without your advice and assurance. It was amazingly easier than I ever expected. The modular design of the Corsair PSU was also a big plus. The other type with what seems like a hundred wires has always scared me off from thinking that I could replace a PSU. I also can't get over how quiet the Corsair PSU is.

Well, I just wanted to report back that everything is running fine once again. I have my computer back and it's better than before. Can't say enough how much I appreciate the help!!


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#12
May 18, 2013 at 19:51:50
You are quite welcome and thank you for letting us know.
If you can choose a best answer and indicate it 'Solved' it will help also.

You have to be a little bit crazy to keep you from going insane.


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#13
May 21, 2013 at 14:14:23
I thought that everyone.s responses were helpful, however OtheHill's information and assistancet would rightly be the advice that solved the problem I was having! :-)

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#14
May 21, 2013 at 16:41:22
If you click on "Best Answer" for the one that helped you the best, the post will then be reported as "Solved".

You have to be a little bit crazy to keep you from going insane.


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