# [solved] HP 2540p: CPU temp, fan, thermal trip points, etc

## Joseph K.

In a display of great contempt, my laptop has started to overheat (and power-off) when doing anything CPU intensive such as compiling the kernel.

It just started doing this in the past week or so, and I can't think of any reason why, so I'm pretty frustrated.

I never examined what was going on thermally in the past when there was no problem, so I can only report on how things are now.

All the thermal and cooling monitoring is via ACPI, I don't have lm_sensors installed and I'm pretty sure that sensors-detect finds nothing useful.

Thermal Zone (TZ) 2 appears to report the CPU fan speed: it moves in steps and matches the sound of the fan.

The CPU idles at about 45°C with the fan at 10, sometimes 0 (whatever the fan units are... %?), which seems reasonable, but I'm not sure.

When I compile the kernel, the CPU rapidly hits ~90°C and I hear the fan rev up several steps.  TZ 2 has these steps: 0, 10, 21, 37, 53, 70.  But even at 70, the CPU temperature ultimately hits 100°C, which I'm pretty sure is close to the critical power-off point (which is ~105°C).

I am doing a lot of Googling at the moment, but I thought I would put my cry of anguish here in case anyone can tell me anything useful.  Like, do those CPU temperatures sound normal or abnormal?  Should the fan steppings go higher than 70?  Is there a known glitch in thermal stuff in the kernel recently?  I don't really suspect the kernel, as I have been using 3.4.x for some time without this problem.  Can I manually try setting the fan above 70?

Oh yeah, it's an Intel Core i5 580-M.  I have tried the acpi_osi=Linux boot parameter to no avail.  The fan is clean.  Any help appreciated.  Thanks, cheers.Last edited by Joseph K. on Mon Nov 12, 2012 4:52 am; edited 1 time in total

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## CkoTuHa

HP stands for "Heat Problems"  :Smile: 

But, jokes aside I see that HP 2540p is HP's pro line(competition to dell's and ibm/lenovo's rugged nb lineup). It should have better cooling design than the consumer grade laptops. I am running T400 here ( Core2 T9400, 2.5GHz machine ).

I was torturing the laptop with intel's linpack_10.3.10 and I found that it can overheat the CPU to the point where the OS shutdowns if I hold laptop in somewhat tilted position. My guess is that hot air is vented somehow and gets into the fan somehow if I tilt it a bit. But it works fine in case I put it on a level, flat surface, like a table top for instance.

It idles at 34-38 degrees:

coretemp-isa-0000

Adapter: ISA adapter

Core 0:       +35.0°C  (high = +105.0°C, crit = +105.0°C)

Core 1:       +35.0°C  (high = +105.0°C, crit = +105.0°C)

thinkpad-isa-0000

Adapter: ISA adapter

fan1:        2998 RPM

temp1:        +38.0°C

Compiling kernels is not a big deal as it never manages to heat up the chip as linpack does.

I also I had a fan fail on me. It would stall after s2ram. The way I cured it sprayed some engine oil on the fan bearing and it worked. I applied AS5 as the oem thermal compound is some fancy gum. It probably doesn't conduct heat well as I noticed as soon as I replaced the thermal compound the temps dropped 10 degrees under load. From 90 to 80. So this is my story with the laptop cooling. Btw, I find that tp have good cooling designs and for the most part work nicely. So my suggestion(perhaps too late) is to replace the oem thermal compound. I bet it is shitty one.

Oh, and I never bothered with the available tp-fan-control.

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## Joseph K.

Hey, thanks for the reply!  It was a hardware problem after all: replacing the fan fixed it.  Cheers.

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