Core i7-980X: Dialing In Efficiency With The Right Overclock

Conclusion

The new 32 nm, six-core Core i7-980X is a great performer—no surprise, right? However, it offers much greater flexibility than previous multi-core products. For starters, it comes with Intel’s Turbo Boost feature, allowing it to accelerate by one or two clock speed increments depending on the workload. The fact that this is an Extreme Edition part allows the user to alter not only processor multipliers, but also the maximum Turbo Boost speed settings for each number of active cores.

By taking advantage of this flexibility, it's possible to achieve much higher processing power, particularly for single-threaded workloads, without having power consumption go through the roof. We found it particularly interesting that system idle power at both overclocked and stock speeds remains constant, proving just how quick Intel’s on-chip power management is at switching off unused parts of the CPU.

In our testing, we increased the Turbo Boost multipliers, but we kept the same proportion Intel had chosen: one speed bin up for multiple cores (three through six) and two increments up for a single thread.

This led to a strong increase in performance per watt, so long as we could increase clock speeds without cranking up processor voltage. This increase maxed out at 3.86 GHz, which leads to 4.0/4.13 GHz with Turbo Boost active. All faster speeds still provide more performance, but overall power/performance efficiency starts decreasing. Still, even at 4.13 GHz (4.26/4.4 GHz), we found that efficiency is still higher than at Intel’s default 3.33 GHz stock speed.

We can't wait to see what four- and lower-cost six-core versions of this manufacturing node might enable. Bring it!