Andrew Cunningham, arstechnica, Mini-review: Intel’s powered-up Core i7 Broadwell miniPC, here.
Memory bandwidth aside, the Core i7-5557U CPU in this new NUC is the fastest Broadwell chip that Intel is shipping right now. More powerful dual- and quad-core processors will follow within the next couple months, but so far Broadwell’s protracted, oft-delayed rollout has focused on low-power chips. This is one of the rarely-used 28W variants of Broadwell-U (most are 15W chips, including the one in the Core i5 NUC), and the more generous thermal envelope gives it some extra room to stretch its legs. It’s got a 3.1GHz base clock (up from 1.6GHz in the i5-5250U) and a 3.4GHz Turbo clock (up from 2.6GHz). The Turbo number is the most important one to pay attention to, since it’s going to dictate how both desktops perform in general use.
The Core i7 NUC is around 25 or 30 percent faster than the Core i5 version, which is a nice speed upgrade. It’s still no match for the quad-core Haswell Gigabyte Brix Pro in multithreaded tests, which shouldn’t surprise anyone. Under sustained load, the Core i7 NUC’s clock speed settles somewhere in between 3.1 and 3.2 GHz—it can’t sustain those Turbo Boost clocks for long. By contrast, the Core i5 NUC can stay at 2.4GHz pretty much indefinitely.