Hello!! HELP!!

I am using Maya on 400mhz G3 ImacDV Special with 512mb RAM with ATY
Rage 128 graphics card.
Everytime I use CV curves or EP curves and try to manipulate and move
points the macintosh crashes and I have to reboot. Also when moving
any NURBS object or rotating it crashes also.
Is there anything I can do to resolve or help situation.
It renders fine and everything else is smooth..

Thank you