I have noted that from time to to time that not all of my CPU cores are being utilized which seems odd at time but for a game; I would expect all the cores to show some sign of activity.
Here are a couple of things to check:
1) Also there is a chance that your software isn't reporting the core usage correctly? There is a gadget out there that does monitor the core activity (sorry, don't remember the name).
2) Have you checked the BIOS under the Advanced page to see if CPU Core Activation is set to Auto? It may be worth a look in the BIOS to see if you can manually "force" the cores on if the Auto function isn't working.
3)Another thought...you mentioned Overclocking? It may be that the added clock frequency may be too high for all of the cores to support (taking a guess here; I'm not a OCer and you may want HiVizMan or some of the other expert OCers to chime in) as you may want to lower the clock frequency back to the default.
Keep us posted
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For trouble-shooting tips see my blog at:
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http://thenerdbench.blogspot.com/p/bench-testing.html
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MB: Crosshair V Formula-Z • CPU: FX-8350 • GPU: Asus Matrix R9 280x • RAM: 8GB of Crucial Ballistix Tactical Tracer (1866)• PSU: Thermaltake DPS Thoughpower 750 Watt • CPU Cooler: Thermaltake Frio Advanced • Keyboard: TT Sports Challanger Ultimate • Mouse: TT Sports Black Element • Case: Thermaltake GT Level 10
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