I don't think this can be the reason, Corsair DDR3 Vengeance is hardly low profile and is easily available at 1866 speeds. The triple channel XMS3 i have on my X58 is the same height and running comfortably at 2150 at 1.68v. If it needed actual blade server like low profile memory, then yes this would be a severe set back to enthusiast speeds, but just no spiky bits?? sounds bearable to me.