paci2020: Tried this but does not prevent the crash. From what i can tell, it happens if you happen to look in the direction of a certain part of inside the mechanist's lair near the entrance where you first use Ada to open up the lair. (At least for me.) It's around where after entering the first zone, you turn left and then left again to see some lockers. The game will crash seconds after looking in this direction. A workaround I've found is to avoid looking in the direction of that locker area. Keep facing the front towards where the decontamination tunnel with the two robot guards are. You can still enter the side side passage to the left just before the tunnel or the security room on the right but do not point yourself in a way that makes the game try to render the locker area behind you. (Eg, I managed to crash the game by sitting down on the chair inside the security room while clicking around for loot around the counter.) Always look away from that locker area and you can get past and the rest of the Mechanist Lair should be fairly stable.
(I still ran into a bug with the mechanist final boss fight where after awhile, the mechanist will stop spawning enemy bots and endlessly spam bombs, mines and tesla lightning. I may have bugged out the game by shooting bots in the manufacturing area as they roll past in the ceiling above me for loot. I had to unlock the side elevator with the three holotapes and avoid the boss battle completely to proceed. :/)
Good luck! Here's hoping the rest of the game works for us.
Mega Man X: Does anyone know how to overcome the game crashing at this point in the game?
TPR: I had the same problem - game crashed every time I was trying to enter "RobCo Sales and Service Center".
Every tip about disabling problematic mod was wrong because I'm playing Fallout 4 without mods (for achievements).
I managed with this problem by lowering graphic settings to "medium" and disabling some other things like anti-aliasing. For this location only. When I finished with mission in Mechanist lair and went back to Commonwealth and then I reverted them to Ultra.
Lowering to "High" didn't helped here. That's why I've set "Medium".
Thanks. Both of the tips above helped me.
I also noticed that when I took a look at the lockers near the entrance the game would crash. So I tried to get past the zone without looking at them but I was not that lucky enough. So what I did in order to get past this area was to lower all of the game graphical settings to the lowest option possible. After that, what I did was to load the game and get to the lair's entrance without looking at the lockers, getting through the hole in the wall and keep playing through the zone normally.
After getting past the tunnel with the lasers area, I was able to look everywhere without the game crashing although I would recommend quick saving just in case.