Fatal1ty x399 won't post with 128GB RAM

Hello,

I've been direly trying to get this to work and so far nothing is working right. 

Here is the problem:

My x399 Fatal1ty motherboard will not post when I have all 8x16GB (128GB) sticks of RAM in it.

The Dr. code thingy shows this error:  C0

SPECS:

Mobo:  Fatal1ty x399 Motherboard
CPU:  Threadripper 1950x
RAM:   128GB of CMK128GX4M8B3000C16 CORSAIR Vengeance LPX 128GB (8 x 16GB) 288-Pin DDR4 SDRAM DDR4 3000 (PC4 24000)   (on the QVL)
PSU:  Corsair RM1000x
GPU:  GTX 1060

DETAILS:

If I put 8x RAM sticks, it will not post.
If I put 1 to 7 RAM sticks in, it posts.
I have tried ALL ram slot combinations.  They all work.
I have tried ALL ram sticks.  They all work.
I have got a brand new x399 Fatal1ty motherboard.  Still has the same problem.
Problem exists in bios 1.3
Problem exists in bios 1.5
I've tried multiple PSU.  All work fine.
I've tried multiple GPU.  All work fine.
CPU looks just fine (no scarring of the plate, brand new).

The issue literally is the 8th stick of RAM causes the system not to boot.  That's it. 

I've tried changing a few things in the bios and nothing matters.  I've reset CMOS and that changes nothing. 

If I put 4 sticks of RAM in, it boots just fine, installs Win, etc.  I've tried all various RAM slots and they all work.  All RAM sticks work as well.

I absolutely must get all 128GB to work.

Does anybody have any ideas what to do?  I can't think of anything else to try.

UPDATE:  The following occurs (and is repeatable)

If I have 7 sticks of ram (to get it to post) and update to 1.5 bios
Then reboot, clear settings, update to 1.3 bios, power down
Then plug in 8th stick of ram
Then power back on...
... the system will boot into Windows 8.1

HOWEVER

Windows 8.1 will say there is 32GB of RAM usable and 96GB as "Hardware Reserved".

If I reboot then the system will never post again with a C0 error.

Something is really messed up.  Again, this is the second x399 board.

It is as if this RAM isn't working correctly with this mobo, yet I know the RAM works fine as 4 sticks works just fine in all combinations of slots + RAM sticks.

Xaltar wrote: I would open a support ticker with ASRock Tech Support. Based on your description it sounds like incompatibility. It technically could be the IMC on the CPU failing to operate with 8 populated dimm slots, it may be worth looking into voltages, you may need a little more to get 8 dimms to operate. Again though, Tech Support is who you want to ask, they will be by far better equipped to help you (they have access to your exact board model to test with).

I emailed their tech support.  They told me to return the motherboard.

So I did and bought a new one (same Fatal1ty x399).  It has the exact same issue.

I've changed voltages and reduced timing down to 1866 and still it won't boot.  7 sticks = POST.  8 sticks = no post.   :(

Contact them again and direct them to this thread. You were likely told to RMA because one of the most common causes for issues like yours is a defective DIMM slot, with that ruled out they should be better able to assist you.

re: CMK128GX4M8B3000C16
I must ask. Is this a 128GB(16GBx8) Kit, or two 64GB(16GBx4) Kits?

If indeed it is a 128GB Kit, check that ALL serial numbers are consecutive.

The rest here assumes all 8 sticks are consecutively numbered !  If not post back, then contact the reseller or Corsair themselves

Is this occurring before or after you set XMP?
Describe please the method you are using to set XMP, as If you just booted into the BIOS.

You don't say what GPU it is you have. One in particular drew(before a vBIOS update) an inordinate and out of spec power draw from the PCIe bus.

Please post what GPU and also try plugging in/powering the 6-pin GFX_12V1 at the lower rt corner.
Connecting GFX_12V1 would be all four MB power  connections: 4-pin(ATX12V2) , 8-pin(ATX12V1) , 24-pin(ATXPWR1) , and lastly 6-pin(GFX_12V1)

Pull all the power connections and look at the mating M and F parts that the connectors are round and inserted to their proper depth in the M ends. I've seen on occasion where one has backed out and did not make proper contact with the F pin.

Also look in the F connectors that the pins are centered. Seen this too where a pin was bent and not sliding into the M's round connector. This usually results in a connection that the M+F connection itself didn't allow for the connection securing clip on the M part to "snap' over and lock onto the F side.

Look at ALL power connections that you didn't inadvertently not get all the M-F connections properly inserted and now have two or more pins not getting inserted into their correct contact. ie: powering air