They are at the edge of current RAM limits of 52-bits (I believe this is the case on both x86 and ARM systems). If they could get a system with the full 64-bit

They are at the edge of current RAM limits of 52-bits (I believe this is the case on both x86 and ARM systems). If they could get a system with the full 64-bits of addressable RAM, they'd likely have gone even bigger.