What is your system? Does it happen for a particular model or just 'empty' viewer? Do you have any other applications running? Could you check in the Task Manager what happens with the available memory size in this time. Does it change?
I use Win 7 sp1 64bit, and RSAP2012 x64, i usualy get fatal eror when i have opened some model but i think that several times that happened with 'empty' viewer.
Other applications running at that moment, hmmm just Autocad?? Same thing happend with RSAP2011 x64.
I have tried to make tests on several computers but there has been no similar problem on none of them. Are you able to send the crash report (the corresponding dialog should appear on your screen provided you agreed to participate in this program)? If yes, could you tell me what email address you typed there so that I could find it please?
Thank you for sending the report. Looking at the information you provided we assume that you had some maps displayed and the Display (attributes) dialog opened. Do you have the same situation when the Display (attributes) dialog is closed as well as no Maps dialog is displayed (in general no dialog with the tab selector on its left hand side is opened)?
Does it make any difference if you reduce the display acceleration to None?