Sudden decrease in performance!!!

Jan 10, 2015
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4,990
Guys i have a serious problem suddenly i had lower performance than before in battlefield 1 i was getting 60 fps low settings now only 35 ac unity i was getting 30 now not even 20 whats going on? i formatted all my hdds, reinstalled os , still nothing could my ram cause the decrease in fps?
i5 4690
7850 1gb
b85m g43
coolermaster b500 ver2