So I just noticed this problem for the first time after hitting 50 and going around to all the new Dungeons I'll need unlocked for the Roulette. When I'm in range of these dungeon entrances (the blue aura-type thingy) my FPS will constantly stutter, but when I run away and no longer have this in range, I no longer experience this.

I've opened up MSI Afterburner while this is happening and when the stutter appears (it only lasts for half a second but happens every few seconds) my GPU usage goes from 95% to about 70% on both of my GPUs. It's a very odd issue and it's not critical, but I'd like to know why it's happening.

GPU : SLI GTX 970 FTW Editions
CPU : i7 4790k OC'd @ 4.5ghz