MDPM 1 isn`t working before i change settings


Dear Sirs! Flashed bioses for low power consumption on my rx 480 4g cards (5 cards). All i have in settings now is Fan 40%, Mem 2000, MDPM 1 (Others r modefied in bios). I have some fealing that MDPM isnt working. With all those settings im getting 660 W on my wattmeter. When im changing fan speed in my settings (doesnt metter how much) im getting 610W but only before reboot. After reboot im getting 660 again. So i need to go to setting and change fan speed for example to 41 (+1%) so setting r changed and im getting 610 watts again. What is wrong?