Overclockers Club published a review on the Kingston HyperX Predator KHX28C12T2K2/8X
A quote from the article:
These modules are most certainly using Hynix MFR series ICs in a single-sided configuration. With this configuration, you get the ability to run high clock speeds with loose primary timings to get you there. With this set, I was able to hit 3024MHz stable enough to run through the benchmark suite and some quick Prime 95 testing. By using the 125MHz strap and tweaking the timings along with the voltage on the DIMMs and memory controller, surpassing 3000MHz came pretty easily. Getting further really needs some in-depth tweaking of the voltages and timings. Unfortunately, performance starts suffering even more so than with the timings setup on the 2800MHz XMP profile. A secondary profile is available that sets the DIMMs at 2666MHz with tighter primary timings using the same 1.65v applied voltage.Kingston HyperX Predator KHX28C12T2K2/8X Review @ OCC