No.
A Creator graphics card would need to be installed into the UPA slot of the systemboard, and the shape and layout of the Ultra-5 chassis blocks all access to that slot.
You can only use PCI cards in that chassis.
<a href="http://sunsolve.sun.com/handbook_pub/Systems/U5/components.html" target="_blank"> http://sunsolve.sun.com/handbook_pub/Systems/U5/components.h tml</a>