Have you tried the NVIDIA proprietary driver, from NVIDIA Website? The last time I installed a nvidia card on Debian I’ve used the executable binary. It’s not as easy as installing from a *.deb package, but it should work.
You’ll need the kernel headers (I would install kernel source as well). -- Paulo Diovani Gonçalves, blog.diovani.com / entbonsai.com / @paulodiovani <http://twitter.com/paulodiovani>