, which is architecturally limited to addressing a maximum of 4GB of RAM Instead, the "useful fix" you are looking for is the 4GB Patcher

By default, FNV is only "aware" of 2GB of RAM. Modern systems and mods (especially high-resolution textures) quickly exceed this limit, leading to "Out of Memory" crashes. This patch toggles a "Large Address Aware" flag that allows the game to use up to 4GB, which is the maximum potential for its engine. The Best Tool: FNV 4GB Patcher

To understand the fix, you first have to understand the problem. Released in 2010, Fallout: New Vegas was designed with the technological standards of its time. Like many 32-bit applications from that era, its executable file ( FalloutNV.exe ) lacked a crucial flag, the "Large Address Aware" flag. This limitation meant the base game could only access a maximum of , regardless of how much memory your system actually had.