Despite the fact this post is old, here are some fresh infos that might help someone: the Memtest86+ version that is shipped with unraid Version 6.11.1 can result in system crashes. My system with a Ryzen 5700G and 2*32GB DDR4-3200 RAM was crashing (reliably repeatable). You should download the newest version (6.0) from https://memtest.org/ and create a USB boot stick (with https://rufus.ie/ for example). No crashes with the newest version in my case. All 64GB passed.