Hardware and software settings carried over from our initial round-up allow me to compare the performance of every tested X99 motherboard to the most recent products. Charts include the three most similarly-priced competitors:
Component-specific benchmarks are the best way for us to determine whether something is misconfigured—which we haven’t seen in a while—or covertly overclocked to win benchmark contests—which we haven’t seen in an even longer while.
Memory bandwidth is the one place manufacturers have some wiggle room for a tiny amount of performance differentiation. The X99 Extreme3 gets about the same bandwidth as the X99 Extreme4 and X99S Gaming 7. Motherboard manufacturers are always trying to balance stability and performance by finding the tightest stable advanced timings for various DRAM ICs, and it appears that the X99-UD4 might have been configured more conservatively.