Ok, so I recently started playing Fallout NV again, and did some things to ensure a crash-free game, or reasonably so. I used to crash 10 times an hour. Since I started playing again, not 1 crash yet up to Vault 22.

I'm running Fallout NV with all of the DLC including pre-order packs. I have it all in.

I'm also running some stability mods:

MMUE - Bug fixing mod

CASM - Save system mod (it's working real nice and clean...no corruptions)

MCM - Mod Config Manager for CASM

NVSE - Script Extender for mod support

NVSR - Removes stutter - Vsync on, capped at 60

DarnUI - UI for PC gamers

I'm running an Asus G73JH notebook:

i7 720QM CPU

Ati Mobility Radeon 5870 1GB

8GB RAM

1920x1080 native res

The only INI changes I made were adding the lines for multi-core CPU support to prevent crashing:

busethreadedai = 1

iNumHWThreads = 2

I added those in both INI files as suggested by so many discussions.

I'm running Fallout NV using Ultra settings, and no AA @ 1920x1080. I tested with High settings and custom settings, but I'm getting 60fps a majority of the time playing the game.

So up to this point...no crashing, clean saves, good frames/performance, and pretty much max quality besides AA. The problem lies now with Vault 22 on lower level with all the plants. My fps drops to 22-25 according to fraps. It feels really sluggish compared to the 60, or at the least 50-60. I've tried changing to medium and high settings to test...I gain 1-2 fps more...so it's not due to the graphics settings. I disabled HDR and nothing. I tried window mode and nothing. I disabled the stutter remover (removed .dll temporarily) and nothing. Nothing I do is changing this fps drop, which is unordinary.

I've also noticed it on other occasions in some interior areas like Helios ONE when in areas with a lot of light, or looking directly into a ceiling light. Also in Repconn as well.

What is causing these massive fps drops in interiors during well lit areas, or vault 22's plant life with hazy air, etc.?

I've tried it all, but I'm getting no results.

Thanks.