Peformance Degrading

[veredaux]

Hey ive build my computer around 2 years ago and it has been serving me well, about 4-5 moths ago ive upgraded my gpu from a r9 270 to a rx 570, it was fine in the first couple of months but lately ive been getting massive frame drops even in easy to run games such as csgo , in deathmatch dust 2 im getting around 40-150 fps , frames always drop to 40 when i encounter more than 3 enemies , my frame usually never drop below 80. Also in Rainbows six siege im getting frame drops to 20s.My cpu usage in csgo is only 80% while in siege it's 100%. My gpu usage is fluctuating around 0% to 30% to 100%, it mostly stays around 0 thoe. Ive tried Formating , defragging my hdd and wipe all the drivers and reinstall them. Any help will be appreciated 

Full Specs:

CPU:X4-860K

GPU:XFX RX 570

MOBO:ASUS A68HM-E

COOLER:COOLER MASTER HYPER 103

RAM:TEAM DARK 8GB(2X4)

PSU:VenomRX 700W 80+

HDD:Toshiba 500GB

[kelvinhall05]

That CPU is bottlenecking the GPU hard.