EDIT: It seems this doesn't work. My Fallout has magically fixed itself and no longer lags which mislead me to think this works. Sorry. I do not know how my NV fixed itself so I can't be of much help.


I'm sure most of you know about the gameplay saving dll fix by now. But if you, like most of us including me, downloaded the dll off of the internet there can be some quirks. One of them being that when you set your settings through the launcher you will notice that the display adapter listed may or may not be your actual graphics card.

If you don't trust downloading a dll file of of the internet and also would like the game to recognize your actual card then follow these steps:

I HAVE TESTED THIS MYSELF AND IT WORKS. LET ME KNOW IF IT WORKS FOR YOU.

1. Update your DirectX by going http://www.microsoft.com/downloads/en/details.aspx?FamilyID=2da43d38-db71-4c1b-bc6a-9b6652cd92a3. Simply download and run this small file from Microsoft to update your DirectX to the most recent version.

2. Once that is done navigate to: "C:\Windows\System32\" (C: = Whatever your system drive letter is)

3. Right-click and Copy the file named "d3d9.dll" from this folder.
OPTIONAL: If you have a 64-bit system you can navigate to: "C:\Windows\SysWOW64\" and copy the same file from there. My system is 64-bit and I copied the "d3d9.dll" file from this folder and it worked for me. I'm guessing and assuming either one will work.

4. Now navigate to your Fallout: New Vegas game directory, which is normally: (Once again, C: being whatever your system drive is.)
32-bit: "C:\Program Files\Steam\steamapps\common\fallout new vegas"
64-bit: "C:\Program Files (x86)\Steam\steamapps\common\fallout new vegas"

5. Paste the file you copied directly into the "fallout new vegas folder." If you want to save the "d3d9.dll" that you downloaded just in case, simply move it to another folder. Otherwise, just overwrite it.

6. Enjoy! Let me know if this works for you!

I don't think the dll file off of the internet has been modified or is special in any way. So using the one originally off of your computer seems logical does it not? I'm pretty sure this should work for you, if not let me know and I'll try to help you.

it doesn't work, I used my own DLL before using the older one supplied online and it didn't change anything. Only with the old DLL did the performance change. IMO the people who had problems (infections) got them from popups and browser exploits on some of the first few hosting sites. If you go to reputable fallout fansites and download from there you shouldn't have any problem.

Well it worked for me. If anyone else wants to try, here's how to do it. I just noticed because when I went to change the options in the launcher it said I had a Geforce 7900 GS. Which is just a little different then the GTX 470 that I actually have. So I replaced the file with my own and the "fix" is still applied. And yes I did lag horribly before the dll fix when looking at NPCs. Now I still run silky smooth, not one hiccup, on maximum settings and with my own dll file. I'm also not saying any of the files off the internet are infected, I just figured everyone would wanna use their own file if it works.

i didnt have any luck

Strange. Maybe my Fallout was magically fixed. It lagged horribly before. One other thing I did was go into the Options on the launcher and changed the "Water Multisampling" setting to low. I'll try taking the dll file out completely and see if I lag again.

yeah, thats probably what you were noticing. You will love the dll performance boost when you give it a try, it improves the performance a ton.

Yes I know, my game was horribly slow before I downloaded the dll off of the internet and it magically fixed it.

But sorry to disappoint you guys but it appears my fallout is no longer lagging. There is no d3d9.dll in my game folder anymore and there is no lag in my game when looking at npcs. I dunno how it got fixed but I just tested it.

What still baffles me is how whoever figured this fix out, well... figured it out. When my game is lagging I don't think to start randomly shoving DirectX dll's into my game folder...
Just seems weird to me.

This fix doesn't work for me, unfortunately. I'm having the exact problems as everyone else, but no results from putting that file in my NV folder. I hope patches or driver updates come soon. If there are any other suggested solutions, let me know!

My specs in case it helps:
AMD Phenom II 940BE
ATI Radeon HD4870 1Gb
OCZ Reaper RAM 4Gb
Windows Vista Ultimate (64 bit)