Simply force AA and AF in CCC ( or Nvidia's whatchamacallit ) and turn off the in game AA and AF.

Before doing above I was getting lousy frame rates...considering my rigs horsepower. 20 to 60 fps...yechh !

Now it never budges from 60 fps...

19x12
4AA ( CCC forced )
16AF ( CCC forced )
V-sync on
All options maxed...

This also helps with the momentary hiccups ....

Game still kinda buggy..quests, inventory etc..but now it runs a lot better.

Wow. This made a pretty big difference for me. A still get tiny blips of lag from NPCs, but my framerate is much improved. Disabled AF and AA and VSYNC in New Vegas options, forced them on for the game in Nvidia control panel.

I don't have exact FPS comparisons, but the game is much smoother now. What the hell, Obsidian?

they gotta fix this with a patch :brokencomputer:

And i tought they're bug testing team where the best

Okay so heres a little fix for partners with more than 2gb rams

Download CFF explorer suite; open "Falloutnv.exe" with it and go to "FileHeader>ClickHere>AppCanHandleMoreThen2GBAdressest" so should boost up your frame rate a lil' more

yea that helped a lot game felt a lot smoother than before using a nvidia card dont know about how it holds up around lots of human npcs but just out and walking around felt a lot better

from what i heard theres should be a memory leak patch later out today; man i can't get to new vegas :bolt:

I don't see how this would help me, considering I don't even have AA on anyway. You'd think I'd be able to enable it with a 5770 but my FPS is bad enough without it.

Tried this with my GTX 260 in the "Nvidia Control Panel" and it helped a little, but it still lags when looking around.
I am changing settings one thing at a time to see if it is only one thing causing lag.

I disabled the ingame AA and AF went to the Nvidia control panel, under manage 3d settings, tabbed to --> program settings --> add tab --> located the exe file --> added --> then applied the changes recommended by the OP plus reduced my Max display to a one level lower resolution than recommended and this thing doesn't even lag in the slightest now.

Thank you OP!

If I do that, steam freaks out and gives me errors. I have to restore a backup copy of the .exe at that point.

In the compatibility thingy in the Nvidia control panel it says "Some objects render at wrong depth. Go to: Settings/Display Crosshair = Off" Seemed to clear out some choppiness for me (not NPC related)

I tried this and no performance increase. :/ Running a GTX 460.