X99 WS-E/10G problems with 128GB

Hi.

In order to have two powerful machines we have assembled two times X99 WS-E/10G with i7-6900k and 128GB of HX430C15PB3K4/64 as it is on the supported memories list.

The problem is that we on both machines can only use 96GB of ram as seen here:


But it can actually detect all the memory modules we do have:



We have tried with bios version 3.20, 3.30 and 3.40. Different frequencies and voltages for the rams. And all the times we only got these 96GB.

Any advise on what to do?

After running with 128GB (seen as 96GB) for around 10-30 minutes in Ubuntu, the system crashed, the bios needed a reset, and now it can only utilize 64GB

Missing memory like that on X99 systems usually means the memory speed is to high, or the DRAM voltage is not high enough. When some tools can detect all the memory, like System Browser, but in actual use only some of the memory is not seen, that is another symptom of this problem.

The more memory you use, the more difficult it is for the CPU's memory controller to deal with at higher speeds. If you check the memory support list for any Intel board, the higher the memory speed is, the amount that may be used is reduced.

Try setting the memory speed to 2133 as a test. Also set all the memory timings to Auto. Find the MRC Fast Boot option in the DRAM Configuration screen, usually at the very bottom. Set it to Disabled, to allow memory training to occur during POST. POST will be longer, so start up time will be longer.

Also try increasing the DRAM voltage by 0.5V.