My game's working fine, if anyone's wondering. The issue I have is a minor, but naggling one regarding image quality, and no, its not tied to just mods, as I'm about to demonstrate

http://i157.photobucket.com/albums/t69/kazumsaru/gridartifacts.jpg

Encircled is what I'm talking about. Unusual grid-like artifacts in supposedly transparent textures like grass or hair. This exact issue never happened in Oblivion or FO3 to me, so I'm left guessing whether or not its something different in the current graphical implementation of transparency/transparent textures for New Vegas.

System specs are as follows:
Pentium DC E5200 2.5ghz (yes, I know, old)
2GB ram
Nvidia 9800GT on 266.58 drivers (same issue happens in previous driver versions, and yes, I know I should update, doing it right now)

Additional info is available on request.

A card as old as the 9800GT may prefer older drivers. I have seen this before with Nvidia and these games that the newer drivers can cause weirdness. If the update does not work, roll back an older version.

Rolling back may not be an option for me, as I also play newer games that have far greater bugs (showstoppers, CtD's, completely black/white/grey screens) if I dont keep within a certain minimum driver version (the one I am on now)

Are you applying any custom Anti-Aliasing settings via the driver-override feature in the NVidia driver settings?