Question Might the CPU temperature sensor be wrong?

May 30, 2019
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Hi guys,

I'm having a weird situation here. I recently changed my motherboard and I around that time I started noticing my CPU's temperatures were higher. It used to be around 35ºC idle and around 50ºC when under heavy load. Now I just turn my PC on and my CPU is already at 46-50ºC and goes up to 61ºC under 60-70% load. At first I thought it might have something to do with my newly bought graphics card increasing the temperature inside the chasis too much... but turns out that graphics card is around 32ºC when idle (ambient temperature here is around 30-32ºC. I removed my graphics card for testing and CPU's temperatures were still the same.

Now, I've tried to have the chasis open and used my hand to feel the air there, but it's not warm at all, it feels cool. Same happens when I touch the heatsink, it feels cool, not warm at all.

Do you guys think it might actually be the sensor failing? or might there be another reason?

For now I ordered some new thermal paste, I think it will be delivered tomorrow. However that temperature issue didn't start gradually, temperature changed drastically in a couple days.
 
So you only changed the MB and kept the same cooler and everything else.

A couple thoughts....

I think there's a good chance that the fan curve on the new motherboard might be different.
This alone would cause it.

Also, make sure your cooler is snug, I've seen this get missed tons of times.

When you changed the MB did you change the paste? I would have.
 
May 30, 2019
7
1
15
Hi Jay,

Indeed, I only changed the MB, everything else was the same. I didn't change the paste as I didn't have any available to replace it (the new one was delivered today and I just applied it around 20min ago).

I made sure the cooler was correctly snug (double checked after seeing your answer, just in case).

After applying the new thermal paste (MX-4) I just see a difference of -2ºC.

I'll try installing the old motherboard to check (it has a damaged RAM slot, the rest of it works correctly), but I'll do it tomorrow as I need to finish a college assignment now.


Edit: Found the cause of the issue! Turns out one of the anchors is damaged and isn't applying the usual pressure, thus leaving a thin layer of between half of the CPU and the heatsink. I tried to fix it temporarily while I get another anchor (or another cooler for all it's worth) and lowered the temperature around -4ºC.
 
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