High CPU usage is the number 1 sign of software conflict. Consider an on-screen-display/overlay software as the likely culprit.

For me, RivaTuner Statistic Server's Vector 2D display mode was causing framerates to hover in the upper-50s to mid-60s. I set it to Raster 3D and FPS went into the upper-90s. In the end, I have disabled RTSS outright until I can figure out why it's interacting poorly with nearly everything.

Go to your driver's options for game profiles. Rescan if you do not see this game. Add it if that fails. From there, force the game to vsync and try playing.

This will stop stutter in most cases where you can maintain vsync framerates. In cases where CPU usage was problematic but FPS was not, this will significantly resolve that issue as well.

One other option that can help both of these problems is, if running Intel processors with Hyper-Threading, to disable Hyper-Threading.

While it's nice, even my i7 6700k's virtual cores are each simply equivalent to a core of a mainsteam CPU from 2009. Early i7s might be running into a single-thread bottleneck as a result. My apparently single-core problems appeared to be RTSS.

Lastly, conside an overclock or a bad automatic setup for your RAM as the problem. I had some timings that caused cache misses but my PC is running better than ever now.

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These fixes apply broadly, so rememeber them for other games designed for older hardware than yours (and even occational newer).
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