After changing HDD, CPU fan goes to 3500 rpm on power-on
I just removed my old HDD, just to install an SDD in the HDD slot, and an HDD (1TB SATA on SATA-to-IDE-cart) in my Optical Slot.
Everything seems to have gone smoothly, except... For seemingly no reason, my CPU fan goes to 3500 (CPU at 30-60°C), and my HDD fan to 1300 (HDD at 50°C). I think, at least the CPU fan shouldn't do so...
I already tried resetting the SMC, and reopened it to look if I maybe removed or forgot to reattach a temperature sensor, but both did not bring any solution at all.