I just bought a 8GB DDR3L So-DIMM from Shopee. The seller said it new and not refurbished. I need to check the memory if got some corruption or unusable memory bits.
By default, after installed Fedora into you machine, it don’t have memtest86+ on grub menu when booted. You need add it manually.
$ sudo memtest-setup $ sudo grub2-mkconfig -o /boot/grub2/grub.cfg