Core Temp running very hot over 90 Deg C

[Baldo]

I have just replaced my Mobo and everything works fine, just as it did before excpet that the CPU is running very hot.

Previously it was running at about 47 Deg C but now its over double that.

The speed and settings seem all the same. Is it a physical issue? That is, do I need to reapply the thermal paste and reset the cooler.

ALL the HW is the same as it was before, the only change being the new mobo.

Are there settings in the BIOS that I need totake care of?

Many thanks as always.
Baldo

[Martin Walker]

First I'd perform a double check with another utility that reads CPU temperatures, just in case your current readout is incorrect for some reason.

Personally I've relied on CoreTemp for many years now: https://www.alcpu.com/CoreTemp/

[Baldo]

Out of the 4 cores at least one of them is close to the max of 100 Deg C. The others are over 90 deg C.

[Martin Walker]

Hmm...

First, double check that you've not got some hidden utility running the cores continuously at 100% (which could well cause temperatures like this).

Then I'd personally investigate re-seating the CPU with a fresh application of thermal paste, after first carefully cleaning off what's already on there so you get a good contact and thermal transfer.

Also, do you have a cooling fan on the CPU as well as a heatsink? If so, it should be spinning up at these sort of temperatures if the BIOS is reporting them correctly.

[Baldo]

The two most CPU resource hungary programs are:
MS Windows Search Filter host
MS Windows Search Protocol Host

these are taking up about 13% - 20% of CPU resources.

Could this be a temporary thing due to the new hardware installed and it will settle down after all the indexing is done?

The CPU has a monster cooler on it, about the size of a 1kg packet of sugar!!! It also has a fan on it, and yes that fan is spinning.

[Hugh Robjohns]

Did you fully clean off the old paste from the processor and heating?

If not, there's a good chance the thermal transfer between the two is very poor despite new paste.

[Funkyflash5]

That sounds to me like bad thermal transfer between cpu and cooler, I would remove it, clean both surfaces, reapply thermal paste and try it again. I can't see where a 20% load should have a desktop at or near thermal throttle.

[Moroccomoose]

Design of thermal management for electronics is my day job. Here is the lowdown for applying thermal grease.

1. Make sure the contact surfaces are clean. Use an acetone or similar to remove all previous residue on heatsink and chip. When cleaning the chip, ideally, you should earth your body to avoid electro static discharge, which can destroy integrated microchips. You can get a wrist strap that plugs to the earth pin of a plug. If you have no strap, you can keep touching the PC case to ground yourself. (It has to be plugged in, BUT TURNED OFF AT THE WALL)

2 apply a SMEAR of thermal paste. Less is more in this case. The thermal paste is there only to fill the microscopic voids on the surfaces of the heatsink and chip,so you only want to fill the voids. You do not want a full layer of paste between the chip and heatsink. Us a 'wipe on, wipe off' technique. Paste is actually a rubbish conductor of heat... YES! a POOR conductor of heat..... Its just substantially better than the conductivity of the air gaps in the voids due to the roughness of the contacting surfaces.

3 when seating the heatsink, take great care to ensure the mating surfaces are parallel and that you get that suction between the surfaces. Then carefully and evenly apply the heatsink retention mechanism. It is easy to apply the load unevenly which can cause one side of the heatsink lift up, or worse, crush a corner of the chip , damaging it.

In terms of which paste to use, it is not that sensitive. In domestic applications you are unlikely to see very significant temp differences between brands, if you have applied the grease correctly, using only enough to fill the voids.

Hope that helps.

Stu.

[Baldo]

Thanks for this guys. Just as an update, temps ahve stabalised around the late 50s early 60s. Although there is a fair bit of variation. They do occassionally shoot up to the late 70s early 80s, (Deg C not musical decades!!!)

I ahve not reseated anything yet. I am just wondering if I need to do anyting now that things have stablised. Or perhaps there is still an issue there that just needs to be optimised.

Will run it for a day or so an see how things are. I will have to open things up any way to install the new RAM in the next couple of days so maybe that will be an ooportunity to reseat things.

[dushmin]

First I'd perform a double check with another utility that reads CPU temperatures, just in case your current readout is incorrect for some reason.

Personally I've relied on CoreTemp for many years now: https://www.alcpu.com/CoreTemp/

The suggestion to use another temperature monitoring tool is reasonable. But i'm seeing that every one is focused upon the same thing that is reapply the thermal paste. One must no rule out the external factors that causes the heat in HW. So before applying the thermal paste one should look for the Cooler seating, cleanliness of hardware, cause more fresh air to rotate in room where the system is. Run the system in clean boot.

[ajay_m]

Although I assume in this case we're talking about a stock cooler on a standard pc motherboard, some pc coolers and most laptop cooling systems rely on vapour transport copper heat pipes. These can lose the working fluid over time. Recently I had this happen on an Acer laptop. Reapplying thermal paste did not resolve overheating and a replacement of the whole thermal assembly was required. Fortunately I was able to pick that up cheap from eBay. Just something to be aware of.