Power Consumption Through Our Benchmark Suite
Now, how does a Haswell-E-based platform's power use compare? All of the benchmarks in our review (aside from the games) are automated, allowing us to track consumption over time as each one starts up, runs, finishes, and hands control over to the next. We can calculate how long it takes to execute the entire suite, average power consumption during the log, and total power consumed in watt-hours.
Intel’s Core i7-3970X broke the LGA 2011 mold by pushing up into the 150 W specification range. At several points during our run, it towers over two other generations of Core i7 flagships. You can see that the fastest Ivy Bridge-E model cut consumption quite a bit.
Meanwhile, Haswell-E trades blows with its predecessor in the power department, but definitely finishes its work fastest.
The Core i7-4790K is clearly a lower-power part, though you pay a small performance penalty for those savings.
Of the ultra-high-end CPUs spanning three generations, Core i7-5960X averages the lowest power use (just barely). Core i7-4790K fares best. However, we expected it to boast even more of an advantage, since the chip’s TDP is 52 W under Haswell-E.
The last processor I ran this analysis on was Intel’s Pentium G3258, which took almost three hours to work its way through our suite. All four of these chips finish in half the time. Core i7-5960X earns the distinction of being the fastest, despite a 3 GHz base clock rate.
When you multiply average power consumption and performance (determined by the time taken to finish our benchmark suite), Intel’s Core i7-4790K surfaces as the winner. Really, this comes as no surprise. The quad-core model is quick, and its conservative thermal ceiling helps keep a lid on average draw.
Flagship-class products commonly sacrifice niceties like value and efficiency. Enthusiasts operating at that end of spectrum demand all-out speed, which is what Core i7-5960X delivers. As Intel’s first official eight-core processor, the top Haswell-E model pares back clock rate in order to duck under 140 W. We've already seen that there’s still plenty of headroom for overclocking though, if you’re willing to top the CPU with a serious cooler. Left in its stock form, the Core i7-5960X beats the -4960X and -3970X by finishing our benchmarks faster at lower average power consumption.