Fallout: New Vegas PC tweak guide

This is a brief tweak guide for the PC version of Fallout: New Vegas, highlighting the particularly useful tweaks. Note these are all personally tested and recommended.

If you are new to tweaking, it's the process of altering a game's settings and files for optimal play (e.g. better graphics, improved performance, etc).

Some of this content is sourced from the Fallout 3 Tweakguide (read that for more extensive options) -- tweaking Fallout 3 is very similar to tweaking New Vegas.

Launcher settings

First let's get the launcher settings out of the way, before moving on to more advanced tweaking. Seemingly, the two most affecting settings in the launcher are Anti-aliasing (as is typical), and [Water Multisampling. Unless you have a very high-end system, it's recommended to set AA to 2 (0 produces very noticeable jaggies, while 4 and 8 settings seem to not offer a major difference over 2), and set Water Multisampling to Low. Doing this, you will likely see your minimum FPS double with generally much smoother performance overall, and no real noticeable reduction in graphics. Just be sure V-Sync is disabled.

Update: As of the 1.2 patch, the d3d9 fix and also Water Multisampling change should not be needed.

Advanced settings

Tweaking is done almost entirely via the Fallout_default.ini file in your \Program Files (x86)\Steam\steamapps\common\fallout new vegas directory. Just open this up with notepad and edit away. The following tweaks apply only to that file. Be sure to use the Ctrl+f search function to find the values.

iPresentInterval=0

At least sometimes, the launcher option for V Sync does not work, so if you'd like to disable it, be sure to set it to 0 here and ignore the launcher if it says it's enabled. V Sync prevents 'screen tearing', but is also typically a big performance hit, not to mention it caps your framerate to 60. It's generally recommended to turn it off for all games unless you experience severe tearing and/or unstable framerates.

If you find your mouse acting funny in menus, add these lines under the [Controls] section:

fForegroundMouseAccelBase=0
fForegroundMouseAccelTop=0
fForegroundMouseBase=0
fForegroundMouseMult=0

Make sure V Sync is disabled for optimal results.

uInterior Cell Buffer=3
uExterior Cell Buffer=36

Change these values if you have 1GB or RAM or more to make use of it for better performance. If you have 1GB, change the values to 6 and 72; if you have 2GB, change to 16 and 102; for more RAM, try even higher values. Specifics are not known, so if you're not an advanced user, it's recommended to stick with the 2GB settings, even if on 4GB or more. Note if you change these settings you should also change the iPreloadSizeLimit.

iPreloadSizeLimit=26214400

This setting can reduce stuttering. For 1GB of RAM, change this to 52428800; for 2GB, change to 104857600. As with the settings above, increase further if you have more memory, but stick with the 2GB setting if you're not an advanced user. Never increase this value beyond 262144000.

bUseThreadedBlood=1
bUseThreadedMorpher=1
bUseThreadedTempEffects=1
bUseThreadedParticleSystem=1
bUseThreadedAI=1
bUseMultiThreadedFaceGen=1
bUseMultiThreadedTrees=1
bMultiThreadAudio=0
iNumHavokThreads=5

Changing the settings above to values listed may improve multi-core performance for those with multi-core CPUs (e.g. it tells various instructions to be assigned to separate cores for better performance instead of a given core doing multiple jobs with lesser performance). Difference is said to be marginal, however.

iNumHWThreads=x

Insert the above value under the [General] section, where x is the number of cores your CPU has. This may prevent freezing at certain points.

Console commands
If you'd like to experiment with console commands, see this section of the Fallout 3 Tweak Guide. To make it easier, try the EasyConsoleCommands mod.

Hope this helps!

JunKx: Glad I helped at least a bit.

No specific place beyond the sections mentioned..generally you put it just below the last value.

Haven't heard of this CPU issue, though for all I know I could be getting it too. The game is multi-threaded...Not sure on how to help. If I come across something I'll let you know.

Edit: I've just tested with Core Temp and it seems to be using all six cores on my 1055t.

As for the GPU, did you try the d3d9.dll fix? It seems to be essential for all ATI users, including myself.

JunKx: I wonder if the problem lies with your unlocked cores? Perhaps the game isn't picking those up as it should. Though that wouldn't really explain why it's at least not picking up a second core. Describe the specific spot you're talking about, please.

I've uploaded the file here for you: http://www.sendspace.com/file/n12qap It's possible because of a known engine issue related to the GPU, the CPU is trying to do that work instead and doing a poor job of it. Just a guess. Anyway, you might be surprised with the results, so try it and see. Use the included readme for proper configuration -- it's easy stuff, though.

I do recommend signing up to NVN later though, and grabbing the DarNified UI mod listed in our wiki while you're at it.

Great to hear! Enjoy the game.

i've tried everything except the dll which i can't seem to get the right one for my card?

i have stuttering when panning with v sync on, when i change the value to zero the stuttering is fixed but i get horrible screen tearing instead. there is not difference in performance even when i switch from ultra to low detail settings.

4GB DDR3 RAM
core i5 750 2.67 GHz
XFX Radeon HD 5770
windows 7 home premium 64 bit

One issue I've noticed with the fix is that turning off Vsync makes it feel like game speed is increased. I don't know if it's just me, but my character moves a lot faster due to this fix. I know it probably has higher frames now, but it looks odder than cool.

I'm glad I stumble upon this post! I tried to play Fallout New Vegas however, I'm having some problems with my screen resolution. I've got an Intel i5 16GB RAM and Nvidia Geforce GTX 460 256bit graphic card. Any available tweak/fix for this thing? I've been looking for some yet couldn't find. Appreciate, your help.