Skip to main content

Mid 2010 Model A1278 / 2.4 or 2.66 GHz Core 2 Duo processor

854 Questions View all

Northbridge 2 temperature sensor fail

Hi guys!

I have a problem with my Macbook Pro. When I start up my Mac fans starts spinning at 6200RPM and it becomes freaking slow, even the cursor starts lagging. I checked the temps on an older iStat, and I find that when the Northbridge 2 shows temp between 30-50 degree Celsius than everything works fine, but when it shows 128 degree the problem happens.

Where is this sensor? How can I fix it?

I attached a picture of the iStat temps, the other 129 degrees doesn't cause the problem as they always show that, only the Northbridge 2 slows my Mac.

Block Image

Answered! View the answer I have this problem too

Is this a good question?

Score 0
Add a comment

1 Answer

Chosen Solution

If the PCH sensor reaches 120+ C. your problem is not the sensor, no more than a wet rag is, when a pipe is dripping. Try dowloading also Macs fan control to get confirmation it’s a temperature issue, but if that’s the case your problem is likely coming from a shorted IC or a power line feeding it. There’s around a number of those boards saying goodbye because of PCH, not a very big surprise unfortunately. A replacement of the chip or the logic board might be necessary.

Was this answer helpful?

Score 3


Thank you for your answer. I have a donor logic board for replacing any chips. My question is where and how to look for the faulty chip on the logic board?


@totyamuri If you have to ask it's very likely you don't have the skills, nor the equipment to replace it. It's the second biggest chip on the board after CPU, with hundreds of solder joints, you'd need a rework station worth a few thousands $/€ just to get it off the board.


@arbaman Thanks for your answer, then my question is: on the board there are 2 large chips, the CPU and the GPU, the GPU has the PCH inside or what?


@totyamuri It's the other way round, PCH handles graphics, backlight, clock and a number of other tasks. That's probably the reason why iStat improperly refers to it as Northbridge, which doesn't really exist as such on that kind of logic board, time for an update for the app ? ;) By the way..I didn't notice it earlier since I relied on your description, but I see the battery sensors show the same temperature, which is a weird coincidence. Did you try running the Mac with battery unplugged from the logic board by any chance ? If not, please try.


@arbaman When the picture has been made there was no battery inside, even the battery is dead which one I have, if I plug it in the temps are the same. The Northbridge 2 not always shows 128°, when I turn on the Mac it shows 30-40°, after some minutes it starts showing 128°.


Show 1 more comment

Add a comment

Add your answer

Attila Tóth will be eternally grateful.
View Statistics:

Past 24 Hours: 1

Past 7 Days: 1

Past 30 Days: 3

All Time: 69