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Why is my PC losing power frequently and suddenly?

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May 25, 2012 6:19:11 PM

Hi all, recently been having an issue with my PC. About a month or two ago, whilst gaming, my PC suddenly lost power, as though someone had pulled the plug. My speakers (powered through the PC), various USB lights and keyboard lights were still on though. I simply turned the PC back on without any trouble, brushing it off as bad wiring connection or something. However, this has been re-ocurring at least once per night ever since.

Anyway, I recently upgraded my Graphics card from NVIDIA 9500 GT to a 450 GTS. After I took out my old card and put my old one in, I tried booting up the PC but it only got the log-in screen before it died. I tried again and the same thing happened, only a little bit sooner. So obviously I was a bit worried about the new card, tried swapping my old one back in, but the same sort of thing is now happening, rendering the PC pretty much useless. Since this I have tried powering up my PC without any graphics card installed, and also took out my TV tuner, and just seeing how long it will last, and the answer is about the same as WITH either of the graphics cards installed!

I've had a few suggestions as to the problem. Someone has suggested that the PSU is not powerful enough, which is what I originally thought. It is a 400W but about 5 or 6 years old, and the minimum for the new 450 GTS card is 400/450 W. However, if this is the case then surely it would work fine with no graphics card installed, or even my old one? Someone else suggested that the PSU is simply faulty, and was made worse by trying the new graphics card as it fried it (or something like that). I have given the PC a thorough clean but this makes no difference. Obviously PSU is a likely candidate for the problem, but are there any other ideas as to what it may be? To finish, please note that I don't really have access to many spare components. Also, here are my specs:

Medion PC (unsure of model)
AMD Phenom X Quad-core 2.2 GHz.
4GB DDR3 RAM.
400W Power Supply.
NVIDIA 9500 GT / 450 GTS Graphics cards.
1x500GB HDD.

I am happy to supply any other Information you may require. PLEASE HELP! Thankyou in advance for any suggestions!
a b ) Power supply
a b U Graphics card
May 25, 2012 6:30:19 PM

Maybe a circuit breaker tripping? But I'm more inclined to agree it's time to replace the power supply. I always use antec, ocz, or corsair for value and performance. Some other brands are overated for their load limits.
May 25, 2012 6:32:02 PM

o1die said:
Maybe a circuit breaker tripping? But I'm more inclined to agree it's time to replace the power supply. I always use antec, ocz, or corsair for value and performance. Some other brands are overated for their load limits.


Thanks, do you have any idea why me trying to use the new graphics card would have made the PSU worse?
Related resources
a c 158 ) Power supply
a b U Graphics card
May 25, 2012 6:36:39 PM

What is the make/model of your PSU?
May 25, 2012 6:42:57 PM

Rugger said:
What is the make/model of your PSU?


FSP 400-60MDN
a c 158 ) Power supply
a b U Graphics card
May 25, 2012 7:47:22 PM

With 27A on the 12V rails, that PSU should have enough power for your build. A picture of the label: http://www.hardwareforums.com/threads/another-possible-...

What OS? Are your drivers up to date? Most recent version of BIOS in place? Can you check the system event log to see if there is an error code associated with the shutdowns?
May 25, 2012 8:03:42 PM

Is it not possible that the power has been reduced over time?

I'm running vista home basic. The drivers for my old graphics card were updated regularly so they should be up-to-date, but I'm not sure about BOIS.

PC doesn't really stay on long enough to check system event log, unless there is a way to do it mid-way through start up? Thing is I don't think an error code would register as I don't get a blue screen or anything, power just cuts out instantly.
a b ) Power supply
a b U Graphics card
May 25, 2012 9:04:17 PM

Yeah capacitor aging is possible. I would just blame the power outage on a crappy powersupply just giving up.

Grab a 500w from Antec, Seasonic, Corsair, PC&C.

You can most likely just grab one from best buy or somewhere, see if it works, if not than take it back and say it didn't work for my pc, I want a refund.

Might ask you to pay a restocking fee but atleast you will whether the problem is your psu or not
a b ) Power supply
a b U Graphics card
May 25, 2012 9:07:49 PM

It is the time to buy a new PSU.

From power supply calculator:
1) your pc w/ 9500 GT, recommended PSU Wattage: 335 W (w/o TV tuner)
2) your pc w/ 450 GTS, recommended PSU Wattage: 408 W (w/o TV tuner)

Also your PSU is not the 80 plus one and 5-6 yrs old, so it can't output 400w. So when you add the new card 450GTS (w/ TV tuner) the PSU will try to work hard to power up the PC, but it maybe work too hard to kill itself or broken circuit breaker.

a c 158 ) Power supply
a b U Graphics card
May 25, 2012 9:18:13 PM

Does the system get past the POST and into Windows?

There is a possibility that it is the PSU, but we need to do some more troubleshooting to narrow things down. Do you have another PSU that you can use to test in your PC? Maybe a friend's PSU?
May 25, 2012 9:57:28 PM

Rugger, yes I have gotten logged in once or twice. Maybe managed to half-load a web browser but then the power would give up again. I definitely don't have a spare PSU, I will have to ask a friend but probably will end up buying one to see if it's the problem, as mouse24 suggested. I'll go out and buy one tomorrow probably, will get back to you if this solves the problem. Thanks for all your responses
a c 158 ) Power supply
a b U Graphics card
May 25, 2012 10:13:55 PM

What are the PSU options in your area? Take a look thru the recommended PSU thread in my signature for some good options.
May 25, 2012 10:26:12 PM

http://www.amazon.co.uk/product-reviews/7135799313/ref=... This one is v. cheap and also has great reviews. Though I've never been that knowledgable about which wires I need from a power supply (eg the 6pin GPU supplement etc.). Not sure if this one would have a 6-pin GPU supplement thingamabob.
a b ) Power supply
a b U Graphics card
May 25, 2012 10:40:49 PM

With power supplies, you get what you pay for. Buying that is like hooking your computer up to a potato then plugging it into a power source, Its not gonna work and it will cause a mess and most likely take some of your hardware with it.

Antec, Seasonic, Corsair, PC&C.
a b ) Power supply
a b U Graphics card
May 25, 2012 11:01:35 PM

You do get what you pay for - sometime good quality PSUs do go on sale though. If it is the psu don't keep trying it over and over again - just asking for more serious problems. I have fixed SMPS on very expensive HP/Agillent lab test equipment by replacing the capacitors(Lucky if that is all that went bad), Capacitors are one of the most stressed component in a psu and they do not fix them selves - they only get worse. Go get a psu that has been recommended to you and call it a day before you do more damage.
-Bruce
a c 158 ) Power supply
a b U Graphics card
May 26, 2012 1:25:48 AM

maylor said:
Well the majority of those are newegg, but I live in the UK and I think that's a US-based company, right?

I am drawn to this one. http://www.amazon.co.uk/Corsair-CMPSU-500CXV2UK-Builder...

The links are for US sites, but they are available in the UK. A great value for the money right now is the XFX Pro 550W for less than 50quid: http://www.scan.co.uk/products/550w-psu-xfx-pro-series-...
It is significantly better than the Corsair Builder Series and costs about the same. 80+Bronze, 5yr warranty, made by Seasonic, rock solid rails, quiet. Has more power than you need and is sufficient for any single-GPU system on the street.
May 26, 2012 9:01:31 AM

dish_moose said:
If it is the psu don't keep trying it over and over again - just asking for more serious problems.
-Bruce


Yep I have stopped turning the power on now, and even disconnected most of the cables in the case, anticipating trying a different PSU.

Rugger said:
The links are for US sites, but they are available in the UK. A great value for the money right now is the XFX Pro 550W for less than 50quid: http://www.scan.co.uk/products/550w-psu-xfx-pro-series-...
It is significantly better than the Corsair Builder Series and costs about the same. 80+Bronze, 5yr warranty, made by Seasonic, rock solid rails, quiet. Has more power than you need and is sufficient for any single-GPU system on the street.


Thanks very much, never come across that one before, looks great. Amazon gives free delivery though :) 
a c 158 ) Power supply
a b U Graphics card
May 26, 2012 12:14:05 PM

Sweet - enjoy that PSU if you get it!
May 31, 2012 9:38:51 AM

Rugger said:
Sweet - enjoy that PSU if you get it!


Hi Rugger, I haven't yet got another PSU to try, so my PC is still 'broken'. I was just reading this thread again though, and thought to ask what else you thought the problem could be, as you didn't seem confident that the PSU was the problem.
What are the other possibilites?
a c 158 ) Power supply
a b U Graphics card
May 31, 2012 12:17:06 PM

I'm going to think while typing...

1. If it was the motherboard or memory, then I would expect the error to be caught at POST, but that's not a given.
2. IF your PSU is operating properly, then I would expect your PC to finish booting if it made it past POST. There isn't really a significant strain/load difference between POST and finishing the boot process.
3. You are getting the same indications with or without a discrete GPU. This tells me that it's not likely a lack of power from the PSU, but it doesn't eliminate the possibility of the PSU being faulty.
4. This still leaves us with a few options; motherboard, memory, CPU (not likely), PSU...and potentially the HDD (less likely since a hdd failure would typically result in the PC freezing instead of shutting down).

A couple of questions for you:
1. Were you receiving any HDD errors or was the PC consistently doing HDD error checks during POST?
2. What is the model number for your motherboard? Read this off of the motherboard.

A few troubleshooting suggestions:
1. I would breadboard the PC for the rest of your troubleshooting. Breadboard: http://www.tomshardware.co.uk/forum/page-262730_13_0.ht... Remove the components from the case completely. Make a note to yourself on the location of the connector for the case power button when you remove it. To start the PC while breadboarded you simply short those two metal posts...I use a small screwdriver.
2. Until you resolve the issue, just use your onboard GPU. Less parts means less troubleshooting variables.
3. Thoroughly inspect your motherboard for bulging/leaking capacitors. Some picture: http://www.google.com/images?hl=en&q=bulging%20motherbo...
Some great info on bad caps: http://www.badcaps.net/pages.php?vid=5 Be thorough...sometimes bad caps are hard to ID.
4. If your caps are good, then boot while breadboarded. If it boots and is stable while breadboarded, then it is your case or something shorting between your case and your other components.
5. If you have more than one stick of RAM, then remove one DIMM and try booting. If you still get the shutdown, then swap DIMMs and boot again. If you get the same results with either DIMM, then memory isn't the issue.
6. If none of the above gets a stable boot, then I would think either the PSU or the mobo is bad. The first one that I would replace is the PSU.
May 31, 2012 2:50:24 PM

Rugger said:
I'm going to think while typing...


Okay so concerning POST... If i'm not wrong that's the beeps at the start when you turn your PC on? Well my PC does actually beep three times... but it has for years now. I'm pretty sure it's a fault with my USB slots, as if i run with no USB's plugged in then it just beeps once normally, or if only 1 then it beeps twice etc. Maybe there's something that could do with fixing there but seeing as it's been happening for at least a year I fail to see how it could be causing the power outages, so I'm inclined to ignore that until I actually get the PC running again.

My PC does boot up fully after POST, as I have said I can log in before it shuts down. However If I try again straight after then it doesn't last as long.. could this indicate a problem with the heatsync on CPU or something?

I've never had any HDD errors (so far as I know).

My mobo model, I'm fairly sure, is a 686 Amibos VV64.

There is no onboard GPU, or at least no outputs for it... It came with the 9500 GT, and there are no other outputs.

Capacitors all look fine, I've inspected them before. No bulges or anything. I'm reluctant to try turning it on 4 times with the different RAM, as I've been warned against keeping trying to turn the PC on, incase (if the PSU is the problem), it gets worse and blows up.
a c 158 ) Power supply
a b U Graphics card
May 31, 2012 3:12:12 PM

Quote:
Okay so concerning POST... If i'm not wrong that's the beeps at the start when you turn your PC on? Well my PC does actually beep three times... but it has for years now. I'm pretty sure it's a fault with my USB slots, as if i run with no USB's plugged in then it just beeps once normally, or if only 1 then it beeps twice etc. Maybe there's something that could do with fixing there but seeing as it's been happening for at least a year I fail to see how it could be causing the power outages, so I'm inclined to ignore that until I actually get the PC running again.

Agreed - I wouldn't be concerned with this. I would remove any unnecessary components that you have plugged in to USB ports.

Quote:
My PC does boot up fully after POST, as I have said I can log in before it shuts down. However If I try again straight after then it doesn't last as long.. could this indicate a problem with the heatsync on CPU or something?

This definitely makes me think you could have a heat issue. If that HSF has been on there an extended time, then it may be worth your time to remove the HSF, thoroughly clean any residual thermal paste from the HSF and the CPU, re-apply new paste and reinstall the HSF.

Quote:
I've never had any HDD errors (so far as I know).

Good.

Quote:
My mobo model, I'm fairly sure, is a 686 Amibos VV64. Capacitors all look fine, I've inspected them before. No bulges or anything. I'm reluctant to try turning it on 4 times with the different RAM, as I've been warned against keeping trying to turn the PC on, incase (if the PSU is the problem), it gets worse and blows up.

Glad to hear that about the caps.

Quote:
There is no onboard GPU, or at least no outputs for it... It came with the 9500 GT, and there are no other outputs.

I must have misunderstood you above. I'd just use the 9500GT for now; known good for an extended period of time. Based on your feedback, the next thing that I would do is replace the thermal paste on your CPU HSF. There is something simple that you can do that might easily identify heat as the culprit....simply open the side of the case and point a house fan directly into the side of the case. If that resolves your shutdown issues, then you're overheating. I'd replace the thermal paste either way....the fan may not overcome really poor contact between the CPU/HSF.
May 31, 2012 8:33:52 PM

Rugger said:
Quote:
Based on your feedback, the next thing that I would do is replace the thermal paste on your CPU HSF.
Quote:


Okay so I've ordered some new paste + cleanser etc to re-do my heatsink, but I thought I'd take a look under the fan first just to see the state of the paste. There definitely isn't anything slightly moist down there, it's all white, patchy and clearly needs replacing (in my opinion, it's not how it looks on the videos). Anyway, whilst doing this I noticed that it's pretty obvious the CPU fan is not clamped down properly. It's loose and a bit wobbly, and when I push the clamp down it doesn't apply any tension, so I fear it's not pushing down on the processor very much, maybe resting on top of it at best. Will this affect the ability of the heatsink ?

I think it is EXTREMELY possible that I nudged it and possibly broke the clamp whilst changing the graphics card, as was the original problem! the 4-pin from the PSU to the mobo goes straight over the graphics card and plonks itself extremely helpfully in the far corner of the fan, not in the best of places. However, it gets worse. Medion CPU fans come with one of those long funnel-type addons to the fan, e.g. http://photos.expertreviews.co.uk/images/front_picture_...

So it was very hard for me to get the 4-pin unplugged and I probably pushed the fan out of place. Maybe someone with smaller hands could have got it more safetly, but I myself am a piano and rugby player, so my hands are rather on the large side. My plan now is to order a new, cheap CPU fan. I won't need a very good one as none of my system is overclocked. I'll see what happens with a fan with the clamp properly in place.
a c 158 ) Power supply
a b U Graphics card
May 31, 2012 9:48:46 PM

Quote:
Will this affect the ability of the heatsink ?

Absolutely. There needs to good solid, level contact between the HSF and the CPU. You shouldn't be able to see the thermal paste in between the CPU/HSF - that is completely jacked up.

Quote:
the 4-pin from the PSU to the mobo goes straight over the graphics card and plonks itself extremely helpfully in the far corner of the fan, not in the best of places. My plan now is to order a new, cheap CPU fan. I won't need a very good one as none of my system is overclocked. I'll see what happens with a fan with the clamp properly in place.

I would get a 4-pin extension cable to prevent the cable from binding on the HSF and make cable routing a bit easier. Are you planning on getting a new fan or a new heatsink/fan?

Quote:
However, it gets worse. Medion CPU fans come with one of those long funnel-type addons to the fan

I'd remove the clunky funnel and install a fan on the rear of the case. In your picture you can see the honeycomb where you mount the case fan directly to the left of the HSF funnel.

Quote:
but I myself am a piano and rugby player

I'm a tight-head and you don't want me to get my paws near a piano. ;) 
June 1, 2012 11:03:24 AM

Rugger said:
I would get a 4-pin extension cable to prevent the cable from binding on the HSF and make cable routing a bit easier. Are you planning on getting a new fan or a new heatsink/fan?


Very good idea! I forgot they even existed, I've never needed to buy one before. I think I'll get a new heatsink and fan, they've never been replaced after all and I guess 4 years is a long enough time for them to start waring out.

Rugger said:
I'd remove the clunky funnel and install a fan on the rear of the case. In your picture you can see the honeycomb where you mount the case fan directly to the left of the HSF funnel.


I'm not really sure how to get the funnel off so I'll just be buying a new HSF. That isn't actaully my PC by the way.
a c 158 ) Power supply
a b U Graphics card
June 1, 2012 12:00:36 PM

The HSF should last the life of the PC if it gets cleaned every once in a while. The possible exception being the fan. If you want to avoid the cost of the HSF, then I would remove it, reinstall, and make sure that it will still remain securely mounted without the cable installed/preventing proper seating. Don't start the PC until you get the new paste and do a proper install, but you can check for the secureness of the install.

If you don't want to bother with the funnel fan setup that you have, then consider this as a replacement: http://www.scan.co.uk/products/arctic-cooling-freezer-7...
Quality, quiet, inexpensive HSF...you'll need to make sure that you have enough space to mount it. A great little review site that specializes in HSF is Frosty Tech. They have a Top 5 HSF and a Top 5 Low Profile: http://www.frostytech.com/top5_lowprofile_heatsinks.cfm
June 1, 2012 12:50:53 PM

Rugger said:
The HSF should last the life of the PC if it gets cleaned every once in a while.


Cleaning... yeah about that...

Arctic 7 Pro looks good, I saw one of that make in a newegg vid once. It should fit my case, it's quite 'wide' so the height shouldn't be a problem. So let me clarify (I'm not really a specialist on heatsink fans...), You can either buy a Heatsink replacement (the metal bar bits) or a fan seperately?

And the Arctic 7 pro, will that come with it's own support bracket ?

The problem with my fan currently is that, when I nudged it (as explained earlier), the metal strip that runs through the heatsink to attack the fan to etiher side of the bracket bent, so that It won't fit on both sides anymore, making it unstable.
a c 158 ) Power supply
a b U Graphics card
June 1, 2012 5:53:32 PM

the mounting hardware for your current HSF is probably proprietary to work with your spiffy funnel. If you wanted to just replace that, then I would assume that Medion would want you to pay thru your teeth for the new hardware...i'd be willing to bet that they want a minimum 10 Quid for the hardware/shipping.

The Arctic 7 Freezer Pro will come with all the new mounting hardware required to install the HSF. It's compatible with AM3, AM2+, AM2, 939, and 754 so it will work with your Phenom. A new fan mounted on the rear of the case would really help exhaust hot air out the rear of the PC....just measure the screw holes to figure out what size fans it takes.
June 2, 2012 2:39:56 PM

Rugger said:
the mounting hardware for your current HSF is probably proprietary to work with your spiffy funnel. If you wanted to just replace that, then I would assume that Medion would want you to pay thru your teeth for the new hardware...i'd be willing to bet that they want a minimum 10 Quid for the hardware/shipping.

The Arctic 7 Freezer Pro will come with all the new mounting hardware required to install the HSF. It's compatible with AM3, AM2+, AM2, 939, and 754 so it will work with your Phenom. A new fan mounted on the rear of the case would really help exhaust hot air out the rear of the PC....just measure the screw holes to figure out what size fans it takes.


Hiya Rugger, thanks for your advice, you have saved me a bunch of money to be honest. Went out today and got myself a new Heatsink + Fan + a Fan for the side of the case, as well as some new thermal paste + thermal paste removal stuff. Installed the new fans (this one clamps down properly), and I am now typing from my usual PC :)  All is working fine. So I guess it wasn't the PSU which I thought it was originally! Instead of paying about £50 for a PSU I spent £15 and it's working great! Thanks once again
a c 158 ) Power supply
a b U Graphics card
June 2, 2012 4:27:33 PM

You're welcome - Glad we figured this thing out and were able to save you some money!
!