I've had the dim dissapearing problem with SW 2006 also. I also have a nVidia card.
I found out how it was happing though, if I want to edit a sketch and I'm not in the plane of the sketch the dim will not appear (even after selecting the proper plan after in side of sketch edit). To correct...
One of our customers has a special name plate made up that says "Pipe" with the design conditions on it.
Typical design info on their plate is:
MAWP
Design Temp.
Corr. Allo.
Pipe Spec.
If there is not a pipe spec, they usually have some material data on the plate.
We have also performed...