My Macintosh Mac Pro boots from a PCIE solid state drive, and all of my applications are on that drive. All of my photographs are on a four HD RAID5 installed in the four drive bays in the Mac Pro. Since Yosemite OS 10.10.4, whenever I try to open some photographs or import new ones scanned to that RAID, Lightroom crashes my computer. I can access my photos through Finder no problem. So the conflict seems to be between Lightroom and the RAID. If anyone has heard of this problem, please let me know.
If it crashes the computer, it is either a hardware malfunction or a out-of-date/corrupted driver somewhere. If you are trying to import or edit some photos in Lightroom when the problem happens, it might mean that you have defective memory chips, or perhaps a malfunctioning fan, or there is some network incompatibility.
I had a defective front fan. I replaced it and the computer still crashes when lightroom addresses the RAID.