Don`t want to create new topic, but I have some problems with GTA V too.
For me everything works good. Game starts with no crashes, I can see all buildings (no texture lag). Just when I drive a car game starts to lag. Something like a big FPS drop... Each 5 seconds I have this FPS drop :/
Installed disk1 and disk 2 to internal hard drive;
Intalled disk 1 to internal drive, disk 2 USB stick;
Intalled disk 1 to internal drive, disk 2 external hard disk (7200 RPM);
Tryed diferent game realeases.
Still I have the same problem. Maybe somebody has it too? Even google don`t help this time :/