ACAD takes exceptionally long during regeneration ( during full preview or plotting)and then crashes without giving any errors. This happens repeatedly, my files are not that big between 3 to 6 megs, consisting of 3D wireframes with hidden Viewport (mview, shadeplot, hide). I have a P4 3G with 2 G RAM, I don't think my machine is the problem. I have tried to make plt files for various ploters, the result is the same. Any suggestions would be appreciated.