I'm getting code 53 on my x99-a using Corsair Vengeance LPX DDR4 at 2666MHz (4x16gb). All the sticks were in the Mobo's specifically designated positions. Went ahead and unplugged all but one stick, MEMOk'd the mobo and its still at 53. The guy at ASUS said the Vengeance LPX 64gbs weren't on their compatible list but everyone I've talked to has said there should be no issue with this RAM/mobo combo. Can anyone provide any insight here? Should I try different sticks in different positions or are we just dealing with basic incompatibility? Much appreciated.