I have 2 workstations, both 64 bit, 8 megs, less than 6 mos old.
Recently installed Civil 3D 2013 and have been crashing on both machines several times per day for the last week. Productivity is not very good around here!
Autocad sends reports but no one responds.
I've just reinstalled program and also Hotfix 2.
I was only changing raw desc on about 10 points when i crashed this time. DWG is 1.9 megs large - not that big. Sometimes it won't even let me do a saveas, it just crashes!
It's probably drawing specific.
A good way to find out is to export the data you are working with via XML, then import that data into an out of the box template.
Civil 3D 2013 (SP1)
Dell Precision T1650
NVIDIA Quadro 2000
12 GB Ram