Question about heat sensors

My laptop has been running slowly, I managed to fix it temporarily by cleaning out the fan. After a few days the problems restarted.
I've installed Speedfan on my laptop (toshiba satellite a45), and Temp1 the ACPI temperature reading (whatever that is) is 68 celsius. The other readings Local Temp, Remote Temp and HD0 are all between 33-35.

I then installed PC wizard and those temperature readings from that program seem normal (processor and mainboard at 33 and 35).

My question is: what is this ACPI temperature? If it's not an actual temperature, then a) why does speedfan present it as a temperature b) what does it mean that my ACPI temp is so high?

any help would be highly appreciated
-diggyG

 

Speedfan "walks the bus" so to speak. It detects all POSSIBLE sensors, and some of the locations identified may not actually be connected to a sensor. Thus, they can provide anomolous results. The same is true for other programs that ASSUME sensors are in a given location and that they are actually connected to sensors.

In addition, every temperature reporting program can have its own set of look-up tables, calculation algorithms, calibration, etc.

Speedfan has a means to include a + or - offset in the temp reading from a given sensor in the Configuration>>Advanced>>Chip section. For example, in Speedfan I must add a +8 degrees C "offset" to the temp reading from one of my hard drives, to make it display the ACTUAL temperature of the hard drive. The other 4 disk drives in my system have their temperatures accurately reported...it's just that one drive that requires an offset.

One way to check which program may be showing you meaningful data is to let the notebook cool down for a few hours so EVERYTHING in the computer is at about room temperature. Then boot it up and as quickly as possible run the temperature reporting program you want to check.

Now...a processor is going to heat up fairly quickly, but it's unlikely that it will reach 70C within a minute...so if Speedfan reports about 70C IMMEDIATELY after booting up, I'd suspect either the sensor Speedfan has assigned to the LABEL "CPU" is either not connected, not properly identified, or it is miscalibrated.

(while you're doing this, you might as well record all the temps to see if there are other suspicious readings)

Note that initial temperature. Then, put the machine thorugh some hoops and keep monitoring the temps every 2 minutes or so, and see if the way the temps change makes sense to you.

You can do the same sort of rough calibration for any reporting program.

Note that Speedfan (latest version) can now provide TWO "CPU" related temps...the temperature of the processor die (internal chip substrate) and the case temp IF those are available from the computer.

By the way, associating a temperature reading to the "wrong" component is not limited to Speedfan. Other programs can do this as well.

It's up to the user to ensure the right sensors are associated with the right labels, and that the calibration is accurate. There may be fora specifically for your notebook that can help you in more detail.

The Speedfan website has more info on this subject.

Here's one entry regarding ACPI and temperature readings. May or may not apply to your situation, but it's a place to start.
It's from the Speedfan website.

http://www.bugtrack.almico.com/view.php?id=314

Good luck.