I had a similar experience but when I moinitored the system I found it was using all the available memory and then would just freeze.  I have 12gig on board but watched the poser program climb until all the free memory was in use. I used the performance tab in Windows 7 to see this.  I normally have my bucket size set at 64 with no problems but in this case I dropped it to 32 and it rendered OK but even then it was touch and go as at one point is was showing only 100Mb of memory free.  

It could be my set-up is wrong somewhere and it stops Poser using the hard drives as virtual memory I am not that sure but as I have only had the problem on one complex render and therefore I did not research it too much.

 

 

I use Poser 13 on Windows 11 - For Scene set up I use a Geekcom A5 -  Ryzen 9 5900HX, with 64 gig ram and 3 TB  storage, mini PC with final rendering done on normal sized desktop using an AMD Ryzen Threadipper 1950X CPU, Corsair Hydro H100i CPU cooler, 3XS EVGA GTX 1080i SC with 11g Ram, 4 X 16gig Corsair DDR4 Ram and a Corsair RM 100 PSU .   The desktop is in a remote location with rendering done via Queue Manager which gives me a clearer desktop and quieter computer room.