My Lenovo laptop suddenly airs very loud and intermittently. Always 2 seconds, then 3 seconds pause, then again 2 seconds.
Never had problems with the fan, it runs smoothly for years (generally the entire laptop).
What could this be and what can I do about it?
You should once clean the fan thoroughly and watch with a fan tool as the performance is running.
Based on this, the problem can be easily determined.
There may be a dust fan or a problem with the fan control. Take a program like Speedfan to monitor, test the CPU waste heat with Prime95.
Can you recommend me one?
This can be done either on Windows or on fans themselves. Look in the task manager CPU utilization whether the CPU every few seconds in between durably full kanne burdened. If the fan still ventilates so loud despite 1% load, then it puts on fan and would open the laptop case and look at the fan on what it lays. Mostly because of the fact that it has collected so much dust in the fan and therefore it can't be cooled properly over time. That means you have to try to clean the fans.
Capacity at the minimum, everything as always. I'll clean it.
Hardly opened SpeedFan, it stopped, without I have made further settings. Laptop restarted, problem continues nothing more.