Failing hammer test

[ObsidianWraith]

CPU - AMD threadripper 1950X
Motherboard - ASRock X399 tiachie
RAM - corsair CMK16GX4M2B3000C15 (4x8G OR 8x8GB)
PSU - Seasonic Prime Titanium 750W
GPU - ASRock RX580

RAM is failing the hammer test in parallel mode, but not in single CPU mode. What should i make of this?

[David (PassMark)]

There is a discussion of row hammer errors on this page
https://www.memtest86.com/troubleshooting.htm#hammer