BF4 is notorious for making poor use of HyperThreading.
Disabling HT (in BIOS) apparently improves performance in this particular game significantly. It's a very passionately polarized and controversial topic, easy to
google yourself into the thick of it.
I don't play BF4 myself but even though it's a surprising and counterintuitive claim it does still seem plausible. The smart thing to do would be to entirely sidestep the arguments and just compare BF4 performance with HT enabled vs BF4 performance with HT disabled - a couple of system restarts between play sessions would take far less time than a ton of (inconclusive) internet searching, reading, videos, etc. Who knows, maybe this will resolve your inexplicable frame stutters?
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[/Korth]