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High PCH die temperature (Mac Pro 4,1)

Yesterday I upgraded my most recent cMP to dual X5680. I was going to replace the IOH heatsink rivets too, I've had them ready for half a year or so, but could not find them anymore. So I didn't do it.

IOH diode is 77-78°C with default settings, no load. I use MacsFanControl now to up BoostA fan a little. IOH diode sinks to 72°C at around 2000 rpm. Room temperature is approx. 24°C.

When I did the processor swap I looked under the board too, and the rivets seemed to be fine. After reading some of you guys temperatures of IOH/north bridge, I am considering thermal paste renewing and/or thermal pad swap for north bridge heat sink. I wouldn't want to loose IOH chip because of my laziness only.

I think I need to order new rivets, they seem to be buried somewhere too deep in my drawers. I don't think I'm gonna use Zip ties. Any recommendations for good rivets replacements (eBay/Amazon)?
 
mikas said:
Yesterday I upgraded my most recent cMP to dual X5680. I was going to replace the IOH heatsink rivets too, I've had them ready for half a year or so, but could not find them anymore. So I didn't do it.

IOH diode is 77-78°C with default settings, no load. I use MacsFanControl now to up BoostA fan a little. IOH diode sinks to 72°C at around 2000 rpm. Room temperature is approx. 24°C.

When I did the processor swap I looked under the board too, and the rivets seemed to be fine. After reading some of you guys temperatures of IOH/north bridge, I am considering thermal paste renewing and/or thermal pad swap for north bridge heat sink. I wouldn't want to loose IOH chip because of my laziness only.

I think I need to order new rivets, they seem to be buried somewhere too deep in my drawers. I don't think I'm gonna use Zip ties. Any recommendations for good rivets replacements (eBay/Amazon)?
Click to expand...

I would say, your temperature is fine. The chip is specified from Intel to a max of 106°C
When the temperature difference between heatsink and chip is around 10°C, then the thermal paste is fine.
 
W/o fan control: heatsink 65°C/diode 78°C
With fan control: heatsink 59°C/diode 71°C

Difference is bigger than 10°C, it's 12-13°C
The closer the values are, the better the thermal paste, isn't it?
It's not something alarming yet, so I don't have to be in no hurry.

Thank You.
 
mikas said:
W/o fan control: heatsink 65°C/diode 78°C
With fan control: heatsink 59°C/diode 71°C

Difference is bigger than 10°C, it's 12-13°C
The closer the values are, the better the thermal paste, isn't it?
It's not something alarming yet, so I don't have to be in no hurry.

Thank You.
Click to expand...

Difference seems pretty ok. For me it is around 11°C

I monitor my temperature with iStat Menus. There you can setup a notification when a specific temperature on a sensor is measured.
 
mikas said:
W/o fan control: heatsink 65°C/diode 78°C
With fan control: heatsink 59°C/diode 71°C

Difference is bigger than 10°C, it's 12-13°C
The closer the values are, the better the thermal paste, isn't it?
It's not something alarming yet, so I don't have to be in no hurry.

Thank You.
Click to expand...

That's delta T is normal, I don't think change thermal paste or re-do the revet will make any significant difference.

In general, don't fix it if it's working.

But I agree that spin up to fan to cool it down a bit more is a good idea. From my observation, once the NB go beyond 85C, the system may become unstable (AFAIK, the NB chip rated up to 106C only means it should able to survive up to 106C, but not necessary able to work stably up to that temperature). And 78C is not that far away. 71C is a much much better temperature for long time operation.
 
my IOH/north chip seems to float around 70c at low load and drops under load (as fans kick in), is that to high?
(heat sink is about 10c ish lower)
is it even worth me trying to re apply thermal past?

edit lol gess answered, ill let it be,
 
h9826790 said:
28 was the PCIe ambient, system ambient was 26C, you room temperature will be even lower.

I agree that both intake / exhaust was just a bit above normal. But Booster was really way way above normal (even at 100% load)

Even I use my own fan profile (more conservative than the Apple native profile), with system ambient 30C, and keep the CPU temperature at around 78% at 100% load (85C for Apple native setting), my Booster fan still just around 1200 RPM.
View attachment 773422
Click to expand...
Which program are you using to monitor this. I really like the time graphs to the right of the temps.
 
h9826790 said:
Correct, PCH is the Northbridge.

86C is hot. If you already re-apply thermal paste and nothing change, that sounds a bit strange to me.

You may upload the screen capture of the HWMonitor readings so that we can have better big picture to help.

And I assume you already perform the PRAM and SMC reset, but nil help.
Click to expand...


My pc restart 5/10 minutes after booting. Hw.monitor shows PCH Die 120c. Plz help. In real trouble :(
 
h9826790 said:
120C often means the NB rivet is broken. You should shutdown the cMP. Take the CPU tray out to have a look.
Click to expand...

Thanks for ur instant reply bro. But didnt understand these technical terms. What is "NB rivet"
Besides what to do to fix this problem? Because my works are being hampered seriously.
One thing to mention my graphics card is very after restart.
Thanks again
 
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handheldgames said:
With the thermal pad installede with a x5677, I'm seeing better numbers than thermal paste at Idle and under load. There is also a notable decrease in the variance between CPU DIODE and HEATSINK indicating a better cooling with increased thermal transfer.

Pulling the x5677, replacing it with the 990x, it's idling at 32c diode 31c heatsink with the same thermal material. Under full load, 50c diode and 41c heatsink. Adding 2 cores increased temps by 5c on load. The 990x is running cooler on idle than the x5677.

As crazy as it sounds, you just may see better temps with this specific brand of thermal pads.
Click to expand...

So @handheldgames did you use the thermal pads for both the Northbridge and the CPU's or only the Northbridge? I had some speed issues from my PCIe slot 1. As strange as it may sound when I replaced the rivets holding the heatsink (they were not broken but were on the edge) I corrected the 5GT/s speed on slot 1 from 2.5 GT/s with 140 boot ROM. The problem is I don't see any difference in the IOH temperature (75C at idle) so I use the Macs Fan control to lower it down to 60-65C. I know that the spring loaded rivets don't apply enough pressure compared to the Intel design specs in their manual. I think that it will be better to use bolts, but don't know what tightening torque to apply so I avoid this upgrade for now. But it looks like your thermal pad solution works fine. Do you think it is safe to apply 40x40 on all 3 dies?
 
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