Something next to my laptop's processor is smoking when I plug in the charger. What part is this and/or what is the problem? (

XtremeAero426

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I noticed that my laptop stopped charging so I opened it up to diagnose the problem. I originally thought it was either the charger port or the charger but when I plugged in the charger while it was exposed I noticed something start smoking. I immediately unplugged the charger and battery and took a look at what was smoking. It was something within the red box right next to the processor. It wasn't the processor or the GPU as the heatsink was still room temperature. It was definitely one the parts within that red box area because when I touched that area it burned my finger. What part is causing this and/or how can I fix this?

I have a charger with that I can toggle the voltage on and when I toggle the voltage to 15V the power light flashes and that part doesn't start smoking. However, when I increase the voltage to 16V or above, the part starts smoking and the power light remains constant. I'm guessing that it doesn't smoke at 15V because it's not enough to power the laptop but I'm not sure. It was originally charging at 19.5V with no issues whatsoever. I have only tried 15V, 16V, and 18.5V so I'm not sure if it applies only to certain voltages or above a certain voltage.

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System:

Model: HP Elitebook 8470p

Processor: Intel i5 3340m

Video Card: AMD Radeon HD 7570M

RAM: 8GB DDR3

HDD: 160GB HDD

OS: Windows 10 Pro 64bit
 
That 8 pin microchip looks to be what is damaged. What its purpose is is anyone's guess without a cirucit diagram from the OEM.

Also not able to say if the problem is that chip or if something before it broke and is frying it.

Assuming a ivy bridge cpu generation laptop is not under warranty your only sure-fire fix is to purchase a new motherboard.
 

mcnumpty23

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far as i can see charger should be

Input Voltage Range: AC 100V - 240V
Output Voltage: DC 18.5V 3.5A
Power: 65 Watts

hard to tell from your photo but the top of that component looks blistered or something similar--not good i wouldnt think
 

skit75

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It appears that 8-pin IC (possibly a switching regulator) may have blown. The picture is a little blurry but the package appears to be breached, which not normal. The very small coupling capacitor next to it on the left also looks to have heat damage or at least exposed to enough heat for some flux to leach from the solder.

 

XtremeAero426

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What does the 8-pin IC do?
 

skit75

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Without a schematic, it is hard to say. It is likely a voltage regulator\switching supply of some sort. If you do have some soldering skills, you might be able to read model number of that chip and order it from Digi-Key or Mouser and replace it yourself. If you can read the model number on the top still, we might be able to determine what its function is by finding the description\specification data sheet on Digi-key\Mouser websites.