Is this a desktop system? Even though I'm not a big fan of nVidia there is
the nouveau driver. It's reverse engineered and works good enough on older
nVidia chipsets. The current recommendation overall from the experts is to go
with the 9500GT. A number of people here have bought one.
You can find a 9500GT card under Accessories & Other Products:
http://libre.thinkpenguin.com/
Personally I'd recommend upgrading the motherboard or just replacing the
system and getting Intel graphics. They are pretty good now (comparable to
low end nVidia) and certain features are better supported (video
acceleration). Comparatively the 9500GT is about on par with the latest Intel
graphics chipsets.
Obviously the 9500GT is the cheaper option for an older system.
