New Power Supply Pop and then smoke 4

[hubcap1324]

Well I am a Network tech not a PC tech and it may show here......

I leave my pc on almost all the time, well I woke up this morning and that familiar noise I hear every morning wasn't there, my pc was silent. I disconnected the PS from the motherboard just for fun and still no power. The LAN light lights up though but no fans try to power or anything. Obviously it sounds like a PS so I go to Best Buy and purchase a Dynex 500W ATX PS. (My original PS was 420) I plug everything in checked my connections, plug it in and hit the power button. I see fans start to spin and for a seconf I thought all was well, then everything stopped, and a loud pop, then smoke....lol.

System Specs:

Custom build unit MSI MS6570 Mobo, AMD CPU 2600+
3 hard Drives, 1 DVD Burner
Nvidis GeFroce 4 Video 256MB
2 case fans

Incase you are wondering I did ensure the switch on the back of the PS was set at 115 for US....

I am kind of afraid to do much else here like try another PS. Doesn't seem possible to me that an issue with my mobo or cpu could make a PS pop and smoke like that but like I said I am not a PC tech. Possibly a bad PS from Best Buy? It looks like a standard ATX PS. Motherboard issue? CPU? I am kind of stumped here now and hopefully someone here can point me in the right direction....

 

[edfair]

Suspicion that it was bad. Something shorted on the system should cause a crowbar shutdown.

 

[G0AOZ]

Will the store replace it? If not, then a careful look inside the PSU might guide you as to what went wrong. I stress look and not touch, as dangerous voltages can still lurk inside a disconnected PSU. However, you'd need to know what you're looking at!

Other than a visual check inside the PC to ensure that there are no shorts to motherboard tracks, (i.e. loose screw), cut or bare wires, etc., the only other thing to do is to measure the 5v and 12v power input pins on the drives with an ohmmeter to see if there is a dead short to ground.

ROGER - G0AOZ.

 

[paparazi]

I suspect when the original PSU failed it spiked damaging other components which resulted in a short to ground.
Typically the most common component that is damaged is the hard drive, you can sometimes see a burn mark on one of the hard drive PCB's controller chips (a pot mark)
Of course users quite unwittingly install a new PSU, only to find it going pop through no fault of it's own and down to the original resultant damage.
Remove and inspect HDD's
Rom drives can be another component damaged by this type of failure. Martin


We like members to GIVE and not just TAKE.
Participate and help others.

 

[hubcap1324]

Thanks for the replies. Paparazi... what you say makes good sense. My next action was to try another PS (I have a spare at the office that will probably never be used 300 watts and all) but now after this I dont know.

Now, lets say I go and buy another mobo and cpu, is it safe to use the components from the fried mobo? Vid card, hdd, sound card, memory, etc.... Assuming they are ok of course. I would guess also that a new mobo would not be a safe place to test my vid card, memory, hard drives, etc.....

 

[wahnula]

paparazi nailed it. Best case would be a spare PC w/ similar specs that you can swap components on without testing on a newly-purchased rig. There are still C-H-E-A-P MBs available for Athlon 2800 socket A, some with integrated video which is a blessing...for now. If you spend $40 on one of these boards you stand to lose little if a shorted-to-ground components kills it.

I would bench-test a new Socket 754 MB (hopefully w/ onboard video) w/ your trusty 300W, your 2800 CPU, and 1 stick of your RAM. See what happens. If no go then re-think your strategy...trial and error to save an old platform, possible spending hundreds on outdated tech, or entry-level using a more modern platform.

In either case you should exchange your new PSU under warranty. You also need to evaluate what your time is worth to troubleshoot and possibly salvage old components. Sometimes it is best to simply turn your back on an old rig that has served you well and donate it (minus any HD data) to someone who will rebuild it for charitable use and move on to better faster platform, more CPU, more & faster RAM (drool) etc..

Tony

 

[paparazi]

I can give you my experiences when it comes to PSU failures.

Hard drives: very often fail with dead shorts

CDroms: don't fail quite as often and usually just prevent post or booting.

Motherboards: Occasionally fail, simply die, no post nothing.

Processor: extremely rare that they are damaged in any way

Ram: again, very rarely damaged

Other PCI cards: again rarely damaged

Graphics card: also rarely damaged

So.... try the PSU but without any HDD's or roms connected, see if you get a POST.
At least this way you can test to see if moby/CPU/ram are OK
Take out and carefully examine those hard drives
CDroms can usually be attached safely but if damaged may prevent POST/BOOT, it's those hard drives you have to be most wary of.
Martin


We like members to GIVE and not just TAKE.
Participate and help others.

 

[hubcap1324]

Results of my findings:

Took all 3 hard drives out first thing and plugged them in a working pc....they seem to be working just fine as I was able to browse data, open files, etc.

Put memory in a working pc..also worked just fine.

Video Card same thing all is well.

Put spare working PS in my system...nothing at all.

For fun and risky too I might add....I put my "bad" PS in a working PC. Came up just fine except for one thing...the PS fan was not turning.

So now it is down to the replacing the mobo and cpu as it is time for an upgrade. I really am not able to test the cpu since I dont have another system to put it in. My gut says the mobo is gone, and the cpu is just fine.

As far as what happened I assume the fan stopped, the PS overheated and shut itself off..... So how did that damage my motherboard? Maybe the new PS from Best Buy damaged it? I know it was hooked up right since the plugs really only go in a certain way especially.... I remember double checking and making sure all connections were tight.

I appreciate all the responses in helping me solve my problems..

 

[Grenage]

I'm wondering if perhaps you have some sort of short somewhere? I'd give your machine a very thorough check, just to rule that out.

A PSU going *pop* can very easily damage the motherboard, as mentioned above.

Carlsberg don't run I.T departments, but if they did they'd probably be more fun.

 

[edfair]

The pop was something shorting. The power supply probably crowbared to protect itself and the rest of the system.

The fan issue is probably unrelated. Most, but not all, power supplies have a constant fan running off the +12v line and stopping is more from dust or sleeve bearing issues.

The next step would be to check the resistances on the M/B. You can have any combo of things shorted. Supply to ground is one, either M/B or processor. Or the 12v rails in the serial stuff.



Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[c2rich]

I ha this same problem after a while on my AMD system, Here is a quick check, if you have not done so, when you attached the MOB you used screws, some boards come with cardboard washers to prevent shorting, after time theses things can go bad, shift,l or ever you computers worst enemy, dust is causing the short, my suggesting before replacing the MOB is go and buy a bag of cardboard washers from a computer supply store (usually $3-$5) and replace them between the MOB and the screws, even if they appear in good condition try it anyways, with your new PS and the bare minimum (i.e. MOB,Video card,RAM,& Mater Hard Drive) you don;' need sound to test, and see if it works from there, if not then try the MOB. A+ teaches you to replace the cheap simple parts first than if needed the larger parts.

-Kerry

Those that know, do. Those that understand, teach. -Aristotle