fps drops, latency spikes gtx 1060 i5

Hi,

my config i5 3570k @4,2GHZ, 16gb ram, ssd, msi gaming x 1060, 378,92 drivers
i am having serius fps drops 400+standing still drylake, average 150-200 then drops even to 10/20 while casting srs, standing in town not moving i have drops from 150 to 30 :(

witcher 3 ultra/ 2 presets high, no-stable 65-80fps, other games - perfect

anybody have an idea?

with gtx 760 and previous patches/leagues -game was running perfectly;/