Hi, I've been having this problem since the beginning of the year, and even on old editions for some reasons, Aida 64 mixes my CPU OPT fan speeds with my Chassis 1. I've double checked in BIOS and checked my fan cables. My Chassis 1 is a Thermaltake 200mm and my CPU OPT is a Cougar 140mm. Both are PWM fans inserted into PWM headers, with BIOS set to Normal speed for the Cougar, and 2.5 * PWM / C for the Thermaltake.