My laptop had a problem with the heating, when I start Windows it started to work at max RPM (the video card was not showing in the device manager or was shown as an unknown device, every time I restart), after a few restarts within 10 minutes, the fan started working on low RPM, the RPM do change but only in a small border while the speedfan software does not show the RPM at all, the HW monitor software shows something between 2000 and 3000, while the real is much less. I fixed the video card, but the fan problems still persists.

Can you tell me whats going on? Is tha fan burned out, or whatever is controlling it on the motherboard? Since the fan is still working it might be ok, but since the RPM really are changed, I guess that whatever is controlling it is ok, but the current supplied is much less. Perhaps there is a burned defence?

 

Seen several laptops dying from their video processors showing fever. Typically from laptops that have ran even only once on top of beds, blankets... A sure way to kill them by choking the cooling vents underneath.
When choking vents, some sections in fragile integrated circuits get damaged creating more and more heat, ending unuseable and in dumpsters. All for the comfort of users in bed.

Windows OS also forces a bunch of unnecesary applications running in the background pushing processors to their limits and generating extra heat, recognized by the fan speeding up. There is a way to manage some to stay dormant when not needed, but cannot help you with the disabling settings, which if made a certain way, will be stubbornly ignored and reinstated at the next power-up.

 

How do I diagnoze if the problems is in the fan or motherboard? Does anyone know how these fans are controlled?

 

Contact motherboard manufacturer and see if you can get a schematic.

 

That's not likely?

 

Too bad....it's needed to diagnose. Well......if you can't find a schematic......wire fan straight to the proper power supply voltage.

 

Too bad....it's needed to diagnose. Well......if you can't find a schematic......wire fan straight to the proper power supply voltage.

I will try for the schematic. I also have a phone charger which should be able to run the fan,

 

If the laptop is turned on and kept doing nothing at all for a while, the fan should be at slow speed, in my opinion. If it speeds up, the temperature sensing of the unit is telling there is a circuit at fault generating heat.
If the 'doing nothing' condition can be achieved just held at the BIOS screen to ensure the operative system is not operating; it would be even better to evaluate heat generation by observing the fan speed in that idling condition.

A fan running fast at 'do nothing idle' shows a hardware failure in my opinion. Measure the temperature of the exiting air. If you can compare with a similar laptop in equal operating conditions (and ambient temperature) , the fan is doing its work.

If the fan speeds up when exiting BIOS, the processors are to suspect, by either self heating or over processing from too many things running. A fan speed is controlled by a simple circuit with its temperature sensor(s)
Hope gives some clues.