All I know is the 7.5 way, not sure if it's the same in 7:
right click part
select "edit display..."
in the part "shaded display" slide the translucency slider to the right
NX 7.5.5.4 with Teamcenter 8 on win7 64
Intel Xeon @3.2GHz
8GB RAM
Nvidia Quadro 2000