Fixed my performance issue entirely.
Get the d3d9.dll file from New Vegas Nexus and drop it into your Steam/steamapps/common/fallout new vegas folder.
If it's in the right spot when you next launch the game it will re-detect your hardware settings (and probably set them to Medium regardless of hardware). Re-configure your graphics settings in the launcher, then go.
Runs exactly like Fallout 3 now. All of my weird slowdown (like the Primm casino I was complaining about) is 100% gone.
Edit - Added direct link.
Edit #2 - In case anyone is wary of using this, it's totally safe. I can confirm that the file itself is clean, and it's just a file that will basically spoof your video card ID. This problem actually existed back in the original launch of FO3, can't believe it's back again.
Get the d3d9.dll file from New Vegas Nexus and drop it into your Steam/steamapps/common/fallout new vegas folder.
If it's in the right spot when you next launch the game it will re-detect your hardware settings (and probably set them to Medium regardless of hardware). Re-configure your graphics settings in the launcher, then go.
Runs exactly like Fallout 3 now. All of my weird slowdown (like the Primm casino I was complaining about) is 100% gone.
Edit - Added direct link.
Edit #2 - In case anyone is wary of using this, it's totally safe. I can confirm that the file itself is clean, and it's just a file that will basically spoof your video card ID. This problem actually existed back in the original launch of FO3, can't believe it's back again.