Curiously, my Fedora Linux Live USB is working just fine. It boots and everything. Didn't try to mount the NTFS partition on the SSD though. And it doesn't have drivers for the wifi, maybe cause it's an old version of the linux live distro I just had lying around. So, I couldn't test everything. But at least there's no problem with the RAM.
With wifi drivers installed it was smooth sailing from there, and my partner now has a working computer again! πβ