No question here - NVidia is the only way to go. All of our video cards are based
on NVidia chipsets, and are all manufactured by Asus.
The type of card you purchase will be determined
by your needs - extreme gaming, video capture and
output, TV-Tuner capability, and so forth. Driver
compatibility is a consideration here - NVidia has
an excellent track record when it comes to very well-written
drivers. Other manufacturers haven't been so lucky.
Always try to avoid lower-end video cards - the loss
of compatibility just isn't worth it.