Regularly defragment your hard drive to improve loading times and reduce lag:
NFSU2 uses an old audio library that conflicts with modern 5.1/7.1 surround sound.
The Fix:
If you still get audio crackle that causes stutter, disable "Sound Acceleration" via the dxdiag command (Run → dxdiag → Sound → Basic acceleration).
Disable any unnecessary programs running in the background: need for speed underground 2 lag fix
Patching the game can help fix bugs and improve performance. Players can download the latest patches from the following website:
The Issue: The game is hardcoded to 4:3 aspect ratios. Running it on 16:9 or 21:9 monitors results in a stretched image or black bars. Attempting to force high resolutions via config often results in menu UI corruption. The Fix: Regularly defragment your hard drive to improve loading
If you are playing on a modern PC (Windows 10/11) with a multi-core processor, this is the single most important fix. Old games often try to use all CPU cores simultaneously, causing severe stuttering and physics glitches.
Steps:
Note: You must do this every time you launch the game.