Coolers always at maximum. Dell Vostro 5470

I know it's an old notebook, lol, but I wanted to use it for studies and work, however, a problem has been keeping me from doing anything: as soon as it turns on, I mean right after the Dell logo disappears, both coolers spin at maximum RPM (they stay at 5000 RPM all the time), this regardless of whether it's connected to the power supply or not, running heavy software and even with a low temperature (from 28 to 35°C). I've tried many things, installing Dell drivers, updating the BIOS, I opened the case and checked if the fans were dirty and they weren't... And another detail is that it has a dedicated GPU, which doesn't appear in the device manager or anywhere else in the system, such as the task manager and HWINFO monitor, nor in the BIOS. When starting the Nvidia driver installer, I get the error that "no Nvidia hardware was found on this computer". And another detail: even when entering the BIOS settings, both fans remain firmly at 5000rpm😥. Thank you for any help and attention, thank you very much.