BF4 don't use 100% of the cpu and low fps with GTX 1060

hi all
i have i5 3470 3.2GHz up to 3.6 GHz
with custom air cooler
8 GB RAm
600 W power supply
i know i have a huge bottleneck due to my old cpu
when i play bf1 the processor goes to 100% and gpu is only 70% and arround 68 fps on medium & high settings
but when i play bf4 the cpu doesn't excess 80% and 50 % of the gpu
with 50~60 fps !!
why the game don't use the maximum power of the cpu ?
note that i play with activated high performance mode

BF1 & BF4 have the same settings
i'm playing on 79 hz so when i activate the v-sync it limits the FPS to 80
i got around +5 FPS when i set the processing priority of BF4 to Realtime but it didn't push the CPU to achieve 90% and i'm sure my PUS is pretty strong
since 2 days i got issue with windows updates due to my antivirus "360 Total Security" it forced me to install updates so i needed to restore the windows without losing personal data

how to push bf4 to use all the cpu power to to get more FPS ?