Does the UEFI Setup (BIOS) and CPU-Z show the clock frequency of your EXPO profile as 3000 or 3003 MHz? I assume AIDA64 is more precise in calculating the clock frequency based on the best (most ideal) latency value encoded in EXPO, that's why it shows slightly higher clock frequency. But, when you calculate latency timings using 3003 MHz, worse values may come out in the end compared to if you based your calculations on 3000 MHz.