This means you have already applied the patch successfully.
This is the only "patcher" you need. It updates the game’s executable to be Large Address Aware, allowing it to use 4GB instead of 2GB. FNV 4GB Patcher on Nexus Mods. fnv 8gb patch fix
Launch Fallout: New Vegas normally through your standard launcher or mod manager (Mod Organizer 2 / Vortex). This means you have already applied the patch successfully
The actual "fix" you need is the , which is considered the single most essential mod for a stable game. Why You Need It fnv 8gb patch fix