I've noticed this too, however my memory usage tops close to 4 Mb
My CPU usage tops about 30%
Never higher on either.
On an I7 2.7 16 Gb windows 7/64 And now Windows/8 without issues
The mor eocmplicated my models became the worse. And then if you had a disagreeable PAZ or CC it would happen more frequently. Worse culprit was in createing print files as these can compound the issue. for example could create one plot but not batch. And other thngs I'd have issue with like items being visible or not are part of the same issue.
