cooler noise

I have a generic cooler(Dex 9100d) and it has 4-pins, so the bios set it as PWM but it was making a lot of noise so i started trying things, when i choose Voltage as the Control Mode, the noise reduces significantly, i don't think it is caused by RPM because i've tested it with Manual RPM...

So i've noticed that my cooler has been acting up lately. Thing is: sometimes, it works completely silently (as it normally does), and if my laptop gets heated it does make a slightly louder sound, nothing too loud (once again, expected behavior), even when I play graphically demanding games/use...

After adding 2 new fans and fixed them from bios and msi custom profile plus the 2 fans that box had (thor series led fans front ) connected on motherboard only for setup rpm , my cpu cooler started making a bad noise even i return it to default mode through bios and msi program especially on...