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How to recalibrate motherboard temperature sensors

  1. Jun 4, 2009 #1
    I recently had a new fan installed on my laptop because the old one died on me, and even though the new fan is working fine I'm having overheating problems now. I didn't know what the problem was at first until I checked my laptops temperature readings using speedfan. At first it made sense that my laptop was turning off from overheating, but after checking out the readings something doesn't add up. The temperature will shoot up from 20 degrees celcius to 100 degrees celcius in less than 2 seconds. At the same time my computer will still feel very cool so it doesn't make any sense. This has never happened before and is very frustrating since my computer shuts down as soon as the temperature reads 100 C.

    Therefore I think that if I recalibrate the temperature sensors either this problem will go away or I'll realize that I finally need a new laptop. If anyone knows any way possible to calibrate the sensors please feel free to give any advice as it is greatly appreciated.
  2. jcsd
  3. Jun 5, 2009 #2
    There isn't a way to recalibrate the temp sensors on laptops. Your only option as far as that would be to solder on a new sensor.

    Have you checked the temperature directly in the bios? If the laptop is shutting off it sounds like the bios could be reading a high temp as well though. It's a possibility that when you reassembled the laptop, the temp sensor wires got crushed or are possibly grounding out.

    Can you actually feel cool air coming out from the rear/side cooling vent?
  4. Jun 5, 2009 #3
    The temp sensor may just be a simple lead that's sandwiched between the socket and processor. If so, it may be a simple fix.
  5. Jun 5, 2009 #4
    The laptop will sometimes have cold air coming out and still say it's overheating. Your answer makes a lot of sense though, since the issue didn't happen until I had my new fan installed. It could be possible that one of the temp sensor wires got crushed.
  6. Jun 5, 2009 #5
    What? No. Unless its a VERY old laptop it won't have a thermocouple between the proc and socket. If its a 775/AM2/AM3 socket or newer it won't even have the space for one. All procs have temperature sensing diodes built into them, there are no wires. Its these sensors that the BIOS and OS read to get the temperature(s) of the CPU. You actually have temperature sensors all over the laptop at the CPU(s), battery, northbridge, and hard drive at least.

    Back to the original question, you can't recalibrate your sensors. You best bet is to flash the BIOS and hope it was a firmware problem. What brand is the PC? Is it a Sony or Dell? What thermal paste did you use when installing the new fan?
  7. Jun 5, 2009 #6
    It's an hpdv8000, it has 2 GB ram, an intel centrino duo processor and nvidia 7600 graphics card. The thing is, whenever it starts overheating I'll notice the graphics on the computer start to slug but everything else still runs fine. Could it be that just the graphics card is overheating? Maybe a bad heatsink?

    In regard to the thermal paste, idk the name, I just know it was grey and is used for most intel cpu's.

    As for the BIOS, I already flashed it, and I still have the same problem so I don't think it's a firmware problem.

    I've had this laptop for only 3 years, when I first bought it I could run games on it for hours and it wouldn't overheat. Now I run more than two applications and it shuts down.
  8. Jun 6, 2009 #7
    This is already well understood. The fact is, he never stated how old the motherboard is. No need to make assumptions on it's age.
  9. Jun 6, 2009 #8
    How much thermal paste did you use? It sound as though the heatsink may not me making a good contact with the cpu surface. At least one possibility.
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