Burnt PSU/CPU Power connector

ProCs1

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Hello guys, i'm in a bit of trouble and would like some help, please.

I was running a xeon x3440 3.6ghz O.C (1.25 on core) on a P7P55 LX motherboard with a 350 watt power supply (yes, i know)

It was running quite fine for quite long untill i started playing asssassins creed odyssey a couple of days ago (which stressed the CPU to 80-90% most of the time)

After a few fun days of enjoying the game, pc started to randomly restart.
I dissassembled everything and reassembled it.

I came across the culprit, a burnt PSU cable for the 4 PIN CPU power connector. I assume the power draw was too much for the PSU cable or the 4 Pin CPU connector and it just burnt. This is what it looks like

https://imgur.com/a/1NHtkcZ

https://imgur.com/a/9XpdoTJ

The PC is working fine as far as i can see (RAM is fine, GPU fine, CPU fine and the pc boots up)

Now, i understand i need to buy a new/better PSU, but the question is, is that motherboard connector fine? (The pc does boot up even with the burnt psu) I mean if i try cleanning it out, won't it work fine with a new PSU again?
How do i prevent this from happening again? As mentioned, my motherboards has only a signle 4 pin cpu power connector, are there any adapters to make it 8 pin to give the CPU more power and prevent the overload of that 4 pin?

I understand that buying a new motherboard with a new cpu/RAM is nice and all, but obviously, the money is tight.
 
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Solution


https://www.ebay.com/itm/PCB-socket-12V-4-pin-ATX-power-motherboard-P4-connector-2-each/173689986553

Loose or oxidized metal contacts inside the connector will usually cause the problem you had. A loose connector can cause arcing that will melt the connector. Reusing a connector that has experienced arcing isn't recommended because arcing causes the conductivity of the metal to be reduced. An oxidized connector will cause...
You are lucky that all that was destroyed is the PSU. Obviously you can try just cleaning the plug but I don't think it will do anything and in the end it will be an electrical hazard. The best thing to do is just replace the motherboard, CPU, RAM, and PSU with something from this decade. What would your budget be for all of the above?
 

King_V

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I had a situation like this once. A friend of mine gave me an old Sony Vaio (2005 era) that wasn't working, Pentium 4 HT 3.4GHz.

Poked around, and found that the 4-pin connector from PSU to the board was burnt, including some burning noticeable on the plastic connector on the board itself. The factory PSU's wattage rating, as I recall, was rather lower than I'd've expected on a system with that CPU.

In any case, took a chance, and tried another (better, and higher powered) PSU. Everything worked. Used it regularly for about a year or two before I moved on to a more modern machine, and was still working when I gave it away.

I can't guarantee that you'd have the same luck... maybe if you have a friend that has a known good PSU that you could try? Although, I suppose there's a possible risk that the new PSU gets fried.
 
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ProCs1

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Jerremy, thanks for the suggestion but for a broke ass student from a third world country it isn't an option at the moment to invest in a new motherboard/ram/cpu.
I'd really rather get this back working again and squize the last juice out of it.
 

ProCs1

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King_V, guess i'll have to buy a new PSU and see if it works, but the thing is, how do i prevent it from overloading again? I mean, if i get a PSU with 8 pin power connector for the CPU, are there any adapters to work with the 4 PIN the motherboard has?
 

ProCs1

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Kos888, as i'm not sure about my soldering skills, i'll probably take it to a local repair shop to get it done for me. Could you just in case please give me a link to the connectors on ebay? Also if there are any adapters to make a 4 pin mobo 8 pin and provide more power, that would help a lot too. Cheers
 

King_V

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I don't know the answer to either of those questions, unfortunately. I assumed the burning was from the PSU being inadequate, and that the heat at the PSU's connector blackened the MB connector.

I just happened to get lucky in that everything turned out to be fine on the motherboard side of things.
 

ProCs1

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King_V,
I see, i just suspect that the power draw from an overclocked x3440 is too much for only 4 PIN on the motherboard and it might burn out even a better PSU with the same circumstances.
 


Most PSUs the 8pin ATX connector is nothing more than 2x 4pin locked together with a plastic piece that should allow them to be split.
 

ProCs1

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Jeremy, yes i do understand that, but what i'm trying to do is add additional power pins to the CPU on the motherboard with some adapter?
So as instead of the motherboard having only 4 pins to power the overclocked CPU, for it to have 8 now
 


https://www.ebay.com/itm/PCB-socket-12V-4-pin-ATX-power-motherboard-P4-connector-2-each/173689986553

Loose or oxidized metal contacts inside the connector will usually cause the problem you had. A loose connector can cause arcing that will melt the connector. Reusing a connector that has experienced arcing isn't recommended because arcing causes the conductivity of the metal to be reduced. An oxidized connector will cause increased electrical resistance that will heat up the oxidized junction to a very high temperature when a high electrical current is drawn through it.

You cannot just add an 8-pin connector to the motherboard because that can cause the copper traces in the motherboard's power plane to melt when too high a current draw is experienced.

Cheap power supply units tend to have poor quality connectors.
 
Solution
One of the things that changes over time is the temperature rating of electrical connectors. Clear ones, white plastic ones and black ones all have different temperature ratings. You need a "quality" PSU for overclocking. Not just more powerful but better overload protetcion.
FWIW i''ve run a QX6800 1.5875V. up to 4GHz on a 4 pin MB connector w/o problems.