970a SLI krait edition

My system is a amd fx 6300, evga gtx960ssc 4gb, 8gb ram, on a msi sli krait edition., Call of duty warzone has random frame dips on anything above verry low settings what can I do to fix that. My ideas where more ram from 8 to 32, a better gpu like a evga rtx 2060 ko and possibly a fx 8350...

my specs are amd fx 6300 asus m5a78l-m/usb3 1tb wd hdd sapphire r7 360 nitro 2gb ddr5 8*2 gb ddr3 1866mhz ram i generally play in 1366*768 or 1600*900 resolution. I have shortlisted zotac gtx 1050 ti oc 4gb , zotac gtx 1060 mini 3 gb and rx 470 4 gb. i would generally like to play at high-ultra...