Darn! Well if disabling some background applications that you aren't actively using doesn't help, you could try the other fix I made for NOLF.
It uses a different method and isn't as extensive as modernizer but it plays the game just fine!
Download the NOLF revival version (Beta 2!), and disable modernizer.rez from Custom Rez (And any other custom rez file!) Then add "-rez lithfix" (not including the quotes!) to your Advanced Command Line.
Speedrunners use this release because modernizer changes things up a bit too much, so it's pretty stable and should work fine!