Hey!
The device manager never seems to work for me either, you should try to just go directly to nVidias website and download the drivers.
Heres a link that I 'think' might be your graphics card. You should verify before downloading.
http://www.nvidia.com/object/winxp_2k_93.71_2.html <----------
Check the accept box before downloading, download and install, follow the on screen prompts