#1 = ASUS M5A78L-M PLUS/USB3 AM3+
#2 (last night) = ASUS 970 PRO GAMING/AURA AM3+

Facts= 
#1 was not an overclocker dream board, although it had ASUS' great BIOS and loadline calibration settings along with three or four temperature sensors including CPU, NB, SB, and another one

#2 replaced #1 after its 4-pin CPU power connector melted and fused itself to the motherboard. Since I didn't know if it was the PSU's or MB's fault, I used the #1 PSU for parts and started an RMA with ASUS. #2 mobo has an 8-pin CPU power connector and is actually designed for overclocking.  Powered by EVGA 600W PSU.


Meltdown=
#1 was rigged with my FX6300 and 8GB DDR3, 500W Coolmax PSU, plenty of cooling, never let anything get >60 Degrees Celcius. I was able to overclock the 6300 from stock 3.5GHZz to 4.2GHz with my water cooler and plenty of air flow through the case. On board graphics. This was the machine I used downstairs to stream games from my "good" machine upstairs via Steam Home Streaming. One day the four pin plug melted into the motherboard. 

#2 (still) has an FX8350 overclocked from 4.2 to 4.4, sometimes 4.55, no more. Prime95'd for at least 12 hours. Vengeance LP DDR3 2x8GB @ 1.8GHz, 1.5V, 10-11-10-30 (manufacturer's settings). M.2 C drive, SATA III SSD D drive, SATA II E drive (2x 1TB HDD RAID 0). Water cooled CPU idles around 12 degrees Celcius. Never seen it go above 55. NB runs hot (up to 60 even with dual fan cooling directed at NB and SB power phase passive cooled heatsinks).
GPU=EVGA 1070SC; Precision XOC for Pascal, latest and greatest drivers and Precision XOC. Max stable overclock= 112% Power, Temp Target set to 92 deg C and prioritized, Voltage bar set to max, GPU clock offset +70, Memory clock offset +700, custom fan profile to keep 40C>GPU<60C.
PSU= EVGA 600W
Last night the eight-pin CPU connector melted the plastic around 3 out of 8 pins. I cleaned it out and now it's working again, but I've downclocked it to stock, turned Turbo back on, etc. Still unsure why these pins keep melting when I keep the sensor temperatures at a very reasonable range. Anyone have any ideas? Really, throw any ideas you have. At the moment I have a fan directly pointed at the 8-pin connector just in case.

ps. #2's loadline calibration settings were set to either extreme or ultra, or the setting that was one below the highest preset. I set the CPU temp limit to 130 or 140, knowing that it would never reach that with my cooling setup. Same idea as the GPU temperature target - higher you set, higher voltage and/or more power gets pushed to the CPU - REGULATED BY LOADLINE CALIBRATION - but I don't think anyone thought about putting some sunscreen on the CPU power connector.

Your comments, questions, or concerns would be much appreciated.
Eren
 
More

I was about to post photos but I don't think there's a need for that any more.  In both cases the PSU plug looked exactly the same.  I wanted to find out whether:
 
1. ON THE BOARD= Male center piece inside the female part gets too hot and heats up the PSU plug & melts the plastic, the piece I call the condom
or
2. The PSU plug heats up on its own and melts the condom. Has nothing to do with the motherboard, GPU, CPU, wherever it's connected to.

Certainly.
 

 
" />
 
" />

definitely pulling to much on that line, as im sure you know electricity creates heat, the more you add the more heat you will get. sounds like the board is pulling more current than those connectors are designed for, which is worrisome that the psu would provide enough to pass the thermal rating of the connector. a higher rated psu may prevent this but if the connector can not handle the increased thermal load of the power then the same thing can happen again. all electrical connectors should have a load and temperature rating and the correct one used. i would contact evga about this so they are aware, even if they dont warranty it at least they will know this could be a issue.

To the OP, you wouldn't by any chance be putting "cheater" wires in the back of the plugs to power other things are you?! Heat makes resistance and resistance makes more heat.... and around and around you go till you melt your plugs off.  :)

j2345912
Man that's some scary stuff. I wonder if your LLC setting is just asking too much of your power supply. I think quadlatte has a good theory there.

thats beyond scary, it's down right dangerous. that could just as easily caught fire, the plastic composite should be rated to not do this. this tells me that either the plug is crap, the PSU is bad or the board is bad (in which case the overload protection should have kicked in on the psu )

moosedoctor

ps. #2's loadline calibration settings were set to either extreme or ultra, or the setting that was one below the highest preset. I set the CPU temp limit to 130 or 140, knowing that it would never reach that with my cooling setup. Same idea as the GPU temperature target - higher you set, higher voltage and/or more power gets pushed to the CPU - REGULATED BY LOADLINE CALIBRATION - but I don't think anyone thought about putting some sunscreen on the CPU power connector.

Not sure how safe that CPU Temp, 130-140 setting is.  You may want to ask Asus if that could be a root cause of the issue.
 
Something else to consider:
 
A loose electrical fitting will get much hotter than a tight fitting. 
 
So, if there is not good contact between pins and socket, resistance is increased = hot spot
 

Gotta love those cheap power supplies.

Sajin
Gotta love those cheap power supplies.

ouch, he was using a evga one lol

quadlatte

Sajin
Gotta love those cheap power supplies.

ouch, he was using a evga one lol

 
Zing.
 

XrayMan
Definitely need a better PSU. This one should suffice:  https://www.evga.com/products/product.aspx?pn=220-T2-1000-X1
 

 
Yeaaa I'm thinkin more like: https://www.amazon.com/EV...ords=power+supply+750w

MSim

quadlatte

Sajin
Gotta love those cheap power supplies.

ouch, he was using a evga one lol

EVGA just like Corsair and other PSU vendors, they sell some bad low end power supplies. Some of the power supplies are on sale for $20-40 all the time (420-600w). At that price point it's hard to have quality parts in them.
 
It's like buying Harbor Freight power tool and thinking it will last after a year two of use everyday.
 
 

XrayMan
 
Definitely need a better PSU. This one should suffice:  https://www.evga.com/products/product.aspx?pn=220-T2-1000-X1

If were going for overkill, why not go nuclear.
 
This one should be suffice: https://www.newegg.com/Product/Product.aspx?Item=N82E16817171104
 
 

very true, thankfully the 500b i bought is holding up well in my itx box

Again EVGA 1600 Watt SuperNova 2 ATX PSU will possible burn your home down and destroy any attached and any adjacent system.  I will attach or send the fire report for anyone that thinks i"m kidding or something.  Cause i am seriously lucky to be alive and EVGA PSUs can and will cause death when used. And then EVGA won't even honor their own lifetime warranty