We saw the huge bandwidth penalty of having only two DIMM slots on a four-channel memory controller, but we also saw how little effect that bandwidth reduction had on real-world applications. The X99E-ITX/ac even won some gaming benchmarks, though we probably could have gotten similar results by dropping any competing samples to a pair of DIMMs.
The biggest deficit of mini-ITX is indeed cooling, as we were forced to use lower core voltage to reach a non-throttled overclock that was about 150MHz lower than what we've seen from larger boards. But we might have been tempted to use lower voltage anyway to improve efficiency in a compact PC.
That brings us to the award discussion. Since the X99E-ITX/ac exceeded our expectations, we could give it our ordinary “Approved” recognition. Since it doesn’t have anything to compete directly against, it can’t win our comparative value “Recommended” award. Our top award, “Choice”, means that a product is best-in-class. There are no other motherboards directly competing with ASRock's X99-based mini-ITX offering. But even if there were, there's a good chance this would be our victor anyway. An impressive list of features (despite limited board space), performance befitting a workstation-class platform and a reasonable price tag earn the X99E-ITX/ac the highest honor we bestow.
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