Originally posted by Millz
As Linus would say, every system is bottle-necked, as the system can only perform as fast as it's slowest component being used in that scenario. I get frame dips while playing Bf3, and almost everyone does (unless you're running Dual 3970X and Quad Titans). So in order to reduce the bottleneck as much as possible, you can overclock your 2500k. But I am talking in the technical sense, when honestly a 670 + 2500k even at stock should run all the latest games (with the exception of perhaps Crysis 3) on Ultra. So you can go ahead and try to overclock your 670 or 2500k and see if that helps.
Do the frame dips happen when staring at a wall? Or do they happen when you are running through a high traffic, explosion ridden area with huge amounts of particle effects? Obviously the FPS is not going to stay constant, you will always get frame dips when gaming and moving through certain areas of the game, also online tends to have lower FPS opposed to campaign, especially on large servers. Try disabling V-Sync for a bit and see what the frame rate is then, and if you want to keep the high FPS without screen tearing, get Virtu MVP (Pretty sure they come on most modern Asus and AsRock motherboards).
You could try to download MSI Afterburner (which you can also use to OC) and check the GPU utilization. Usually while gaming it will be pinned at 99% however it can fluctuate. That's normal obviously, but the GPU utilization should not be fluctuating from say 99% to 33% randomly for no apparent reason, if that is the case the card might be defective (or maybe just needs a bit more power). The GPU utilization will also fluctuate randomly if you hit your VRAM limit, but 2GB should be more than plenty for 1080p gaming.
My monitor is only 60Hertz, and I can't stand tearing so I use adaptive vSync. It does not add any lag in my case so I feel comfortable using it. What I find funny tho is that with vSync off, I get FPS rates between 70 - 80. Why is it that when vSync is on, I can't keep that 60 mark most of the time when the tech clearly handles higher FPS? I'am planning on doing a little overclock, but I need a new cooler first. Was looking at the H70, and if that's what I need I'm getting it tomorrow. I don't want to overclock the GPU before the CPU is overclocked, in case that will add an even bigger bottleneck.
Dips happen often in fast motions like flying helis close to the ground, allot of moving through high detailed terrain and at times it just dips by like 5 FPS without much going on. Certain maps are worse than others. FPS without vSync reaches all the way from 120++(Looking up in the sky), to 70/75 when action is in motion.
Will Evga precision do the job? That's what I'm familiar with..