Saturday, November 3, 2012

MCH OR ICH Heating on Motherboard

Notherbridge Heating upon motherboard.

Southbridge Heating upon motherboard.

There are many desktop or laptop motherboard,on which there is issue with north bridge or southbridge overheating.

These Bridges are all called BGA chipsets.

On some board both gets overheated or on some board any of the one gets overheated.

MCH means Memory controller Hub,

ICH means Input -Output Controller Hub.


The MCH or ICH could be faulty.

Another Reason can be Faulty Power Supply mosfets near MCH or ICH chipsets.

REASON:--  Faulty MCH or its power supply Mosfets.


Test capacitors for ground on base plate of MCH. The non-polar capacitors should only be ground on one side and not both sides.
If you feel any of the capacitor is ground on both sides,then it can be the issue with MCH.In that case,also test the voltages to the capacitor.The non-polar capacitors should give minimum 1.2 volts reading at one side and no reading at other side.If there is no reading,then it clears problem with MCH. In that case the MCH BGA chip needs to be removed and re-balled by re-balling procedure.
Beside MCH there is a power supply mosfet,these mosfets are to supply power to the functioning of MCH. Also check the voltages at mosfet. The minimum voltage out should be at least 1.2volts.,If less that 1.2 volts is coming out,then its issue with MCH power supply mosfet.It has to be removed from board and tested out board.Most probably replacing the mosfet will help.

There are two types of mosfets. NPN and PNP.
Let it be NPN or PNP minimum 240 ohms to maximum 960 ohms should be there while testing mosfets. If the reading is less then 240 ohms then replacing the mosfet is advisable.

If the Power supply mosfet is tested good and non-polar capacitors near and on base plate of MCH are tested good,then its rarely a chance of faulty MCH.
If the MCH is getting overheated and very hot to touch,then,try re-balling MCH and these should help.
If Re-balling is not helping then replacing the MCH chipset is the only option.
REASON: Faulty ICH or its power supply Regulators.


Like MCH have mosfet for power supply. ICH have regulators for power supply.
But on some motherboards there is mosfet in case regulators.So don't get confused.
You can say,some motherboard have mosfets and some have regulators.Its also board manufacturer,what he prefers good,he will use that semiconductor.
Now,if in case the ICH is getting overheat and very hot to touch.Then first check the power supply regulator near ICH,if that regulator is giving output voltage of less then 1.2 volts,then its considered to be faulty.
If the regulator voltage is checked ok,then check frequency for ICH RTC. Its 32 Khz RTC crystal.If the frequency generated by RTC is not giving satisfactory results,then it has to be replaced.
If the power supply regulator for ICH and RTC is checked ok and still the ICH is overheating,then it has to be removed and ICH BGA chip has to be re-balled by re-balling process.
If Re-balling Is not helping then,replacing the ICH chipset is the only option.

These details will help.

For more troubleshooting refer the help links shown below:---

Troubleshoot Dead Motherboard

Troubleshooting NO Display Problem on Motherboard

Troubleshooting CPU Overheating Problem on Motherboard

Desktop Motherboard Cpu Fan Connector

No SMPS Power Good on Super I/O Chip