Dell is well supported with Linux, Redhat is one of the finest Linux distro and nVIDIA has constant updated releases of their driver software: this means that a visit in their website will give you more than what is needed. Use google.
BTW: Linux is not like microsoft windows where a driver for an Xp can fail under Vista. Not so in linux. Most often nVidia drivers that run under Debian distribution can also run under Redhat or Slackware --difference only applies in their build and packaging system-- something that you don't need worry about.
Try the latest nVidia driver with a "_________.run" extension and install it outside X <therefore, in a shell> and you have great chance. Or goto Dell site find out if they provide a prepackaged driver for your hardware.
Hope this helps. Goodluck.