power supply connector burn out

But did you change both the MB and PSU at the same time?

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That's just what I was thinking. Once either the PSU or Mobo plug/socket contacts have been damaged then they will fail to make a good connection with new the hardware, causing heating and more damage ad infinitum. Both PSU and Mobo (or at least the connectors) must be changed at the same time to be sure of a cure.

I have to say I've built systems for 20 years or so and I've only once seen obvious burning on power supply plugs/sockets. For it to happen twice to the OP surely indicates that the fault is being carried on by mixing old and new parts. It would be exceptionally bad luck for the fault to reoccur on completely new hardware.

Either that or the plug isn't being pushed fully home each time, or it's the same make/batch of hardware with a design flaw!

Dave

Looking at the photos, it appears that more than one pin is getting quite hot. You're cooking pin 11, which is one of the 3.3vdc pins, and 5 and 7, which are grounds. Kinda looks like your motherboard is drawing far too many amps on the 3.3vdc line. Find an automotive amps guesser used for measuring alternator current. These slip on the wire, use the magnetic field generated, and do not require cutting the wire to measure the current. Or, you can get a clamp on ammeter than does DC (many are AC only). The specs on the MB should give you a "normal" current value. My guess(tm) is that your MB has some of the infamous counterfeit low-ESR capacitors which are drawing too much current. Look for bulges on the top of the electrolytics surrounding the CPU, or brown goo ooozing from under the caps.

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thanks for the reply.

yes.. ive swapped new motherboards and new power supplies at the same time.id also say i have a few system fans running.

its so sad and discouraging having to buy new parts for my old machine. i think i might just get a new comp soon. but it would be sure nice to know what's going on with my setup.

Apart from poor contact (aka high resistance) on several pins, I'd have to conclude excess current is being drawn on the 3v3 rail. That leaves out fans and every other peripheral.

If this has occurred in the same case with swapping mobo and PSU at the same time, what is the common factor? The case. Maybe there is a metal support pillar being used where an insulated one should be, resulting in a short to ground.

On Thu, 04 May 2006 13:01:49 +0800, budgie put finger to keyboard and composed:

Graphics card?

- Franc Zabkar

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Dunno, Franc. If the first noticeable symptom is the pooter freezing, I'd be surprised if a video card could pull that sort of current off *any* rail without itself showing signs. But nothing's definite.

And by peripherals I really meant off-board loads .... Mind you, one of my kids pointed out that some SATA drives apparently load the 3v3.

Without knowing what computer do you have, we can=B4t produce a valid answer. The power requirements for a Pentium III are way different from the requirements of an AMD Athlon 64, for instance. Also, it=B4s not the same a computer using the motherboard=B4s integrated VGA as other using a state of the art video card, which will demand a lot of electrical power from the motherboard.

Give us a better description of your system including:

a) Processor type and speed. b) Amount of RAM, and if it is in a single stick or a cuople of them. c) Model and brand of video card (if used) d) Quantity of optical drives installed e) Quantity of harddisks installed and their capacities. f) Model and brand of motherboard g) If there are any other expansion cards installed, include them in the descripcion.

I want to thank everyone for the replies. Interestingly, this is what happened to my new power supply. different pins if you look at this picture when compared to my first power supply

ive tried running limited everything.. one drive. one piece of ram and limited graphic card support.

my specs. a) amd xp 2600+ running freq. 2.06. ghz 333 fsb.socket a. b) corsair xms 512 and kingston hyperx 512 running pc 2700 c) pny 6600 gt agp 8x. running dual monitors d) 2 ide harddrives 7200. 1 sata raptor drive. f) original motherboard with problem asus 8 a7n8x regular new motherboard with similar problem foxconn 600a01-6lrs g) xfi sound blaster h )case is antec dont knwo model number but rather old i) power supply. thermaltake xp550 np: 430W old powersupply (from original picture) turbolink cwt 420atx -12v 420 max power. with pentium 4 sticker

the reliability is variable. sometimes i can use it for days. and then it just starts crapping out every hour or so.

i think my first power supply's 5 volts read as 4.5 volts... is that a big problem?

-thanks Peter

One of the power pins on your motherboard or mating lead is making a poor connection and heating things up as a result.

As a result probably both the connector on the power supply and the motherboard are likely trashed and the problem will continue until you replace both.

Graham

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motherboard

The solution is to replace the PSU and the ATX Motherboard connector at the same time, to avoid a repetition of the problem. There is no pint in using a new PSU if the ATX motherboard connector is burnt. Conversely, there is no point in having the ATX Power connector of the motherboard replaced, and continuing to use the old PSU. You really have to change both connectors at the same time.