Question 2 ram modules works, 4 do not works

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I know my motherboard support up to 128GB 4666MHz of RAM in 4 slots, but nothing in B1 and B2 works.

This is what Asus said:
"Regarding the below described case, we kindly inform you that the RAM modules with the referred part numbers have not been officially tested by Asus with your product and therefore compatible to it. "

My question is how then 2 dimms in A1 and A2 works but not in B1 and B2 slots?

This is reply from Kingston, I told them of what my motherboard is and sent them photos of my memories:
"It is unfortunately not possible to install 64GB modules as this is not supported by your system. "

My question is what they mean 64GB modules AS THIS IS NOT SUPPORTED?
To begin with, you are not even using the correct DIMM slots for pairing. Forget anything you THINK you know from the manual, because you are not reading it correctly. It, and all other manuals, are typically misleading when it comes to memory population rules EXCEPT for in the visual diagrams which show actual population.

For two DIMM population you should be using the A2 and B2 slots, which are the second and fourth slots from the motherboard. If you have two matching DIMMs, those are the slots you want to install your memory in. Not any other combination of slots. It does not even matter WHAT motherboard it is. If it is a dual channel motherboard, whether AMD or Intel, from the last ten to fifteen years, you use the second and fourth slots over from the motherboard, Period.

If you are using four DIMMs that consist of two different two DIMM kits, then you would want to put one set in the second and fourth slot, A2 and B2, and one set of matching sticks in the first and third DIMM slots over from the CPU, which are A1 and B1. Confusion exists because motherboard manuals are misleading due to unexact terminology. When it comes to memory population, the second and fourth slots make up one half each of a dual channel configuration. Putting both sticks in the SAME channel, does not result in dual channel operation. So, matched set in A2 and B2. Matched set in A1 and B1.

If you have them installed that way and it still doesn't work then you have one of four problems.

Either there are bent pins on the motherboard, or the CPU cooler is improperly installed and is cinched down tighter in one corner or on one side than the other and is cocking the CPU in the socket, or the motherboard is bad. It's also possible that either the memory is not compatible with your motherboard, and not all memory is compatible with all motherboards, or one or more DIMMs are simply faulty.

That is assuming you do in fact have a BIOS that is up to date. Reading over your initial post I see that you tried using the A2 and B2 slots, only, when you had just two DIMMs, and it didn't work. That tells me either the memory is not compatible or there is a physical problem, like a bent pin on the CPU, maybe a standoff in the wrong place under the motherboard. Could be an issue with the installation of the CPU cooler. We've seen many occasions where that has caused memory issues because it cocks the CPU in the socket and breaks one or more of the contact points from making contact.

Usually though, this is either incompatible memory or a bad motherboard.

Personally, I dislike Kingston because they don't offer a memory compatibility validation chart or utility AND I often find Kingston memory to not be compatible with a number of motherboards. Intel is usually pretty forgiving in this area though, unlike AMD. Still, if the memory won't work in the A2 or B2 slot then something is not just "not working", it's plain wrong. Something IS wrong if you have to use other slots to get them to work and they will not be working in dual channel unless they are installed in A2 with B2 or A1 with B1. On many boards, A1 with B1 won't work unless the other two slots are already populated.


Well, like I said, it had to be a physical problem of some kind if the A2 and B2 slots wouldn't work. A bent pin would certainly do it and that certainly falls under the "broken motherboard" category.

Glad you got it figured out man. Good luck.