The 34x and 36x multipliers were unaffected.įinally, motherboard manufacturers have permission from Intel to really boost clock speeds, if you’re loading XMP profiles. This didn’t actually implement Turbo Boost 3.0-style scaling it just kept the CPU clock from flipping back and forth between two different clock speeds while benchmarking.
When we tested Broadwell-E on a Gigabyte motherboard earlier this year, we had to manually dial in multipliers, only to discover that the 35x multiplier–and only the 35x multiplier–would produce random clock drops unless every benchmark application was whitelisted in Intel’s Turbo Boost 3.0 app. Our Asus Prime X299-A motherboard displayed very different behavior when we tested the Core i9-7900X as opposed to the Core i9-7980XE. We’d expect more variance between the 6700K and 7700K, for example, than between the Core i7-7700 and the Core i7-7700K.Įven more frustrating, this behavior can vary depending on which CPU you’re testing. You can’t assume that a CPU with a high single-core boost frequency also has an aggressive multi-core boost frequency, and you can’t assume that two CPUs with the same or very similar Turbo ranges have the same multi-core boost frequency distribution–though this is typically more of an issue when comparing between two different product generations as opposed to within the same family. The Core i7-8700K, for example, has a peak all-core frequency of 4.3GHz on six cores, which is fairly close to its peak frequency of 4.7GHz for single-core.Īs a general rule, Intel’s higher-end CPUs will boost more aggressively than their lower-end cores, but even this isn’t absolute. This is one reason why the gap between chips can be wider than they’d otherwise be. First, not all Intel CPUs are equally aggressive when it comes to their Turbo scaling, even if they have the same or similar Turbo ranges. There are several reasons to view this change as a negative.