One both P8 and P9 are 32 bit apps no matter if you are running a 32 or 64 bit OS. 

First order of business is to learn to save often.  Two, how many levels of undo do you have in the general prefs?  It defaults at 100.  Lower it as much as you can.  This helps keep Poser from eating memory with the render cache.

Before you attempt to render, save the scene.  Open the general prefs in the edit drop down and clear the undo cache.  This will free up resources that can lead to crashes.

After you save the scene, close Poser.  Leave it closed for a couple of minutes before relaunching.  If you have been working a long time, or it's a large scene, it's sometimes a good idea to reboot the system.

If you have been having a number of crashes to the desktop, you may need to delete the Poser.ini and have it rebuild.  Go into Roaming>app data and locate the Poser folders.  Back up the ini file by renaming it.  Be sure Poser is closed when you do this.  Let the ini file rebuild itself when you next launch Poser.

If this is a constant problem and always comes when you go to render, I'd hazard a guess that you are running out of memory.  Not because you don't have it one your system but because both P8 and P9 are limited by their 32 bit configuration.