[BIG problem help please!]

My pc version of gta vc keeps on crashing and getting this message

[How do you install the nos mod?]

Do you mean just copy and paste in place of the old file? Because i tried that and didnt work?

thanks anyways!

[How do you install the nos mod?]

How do you install the nos mod? I know you have to overwrite one of the files but its not working?!