Change the number on these values (virtual 204800, physical 204800, virtual_optimised 204800, physical_optimised 204800) to '409600'. However there are some ways to improve performance. even on a top end modern PC you're going to get stuttering and FPS issues.
The GTA 4 Steam edition was re-released in 2020 to remove the outdated and buggy Games For Windows Live sign in, the addition of Steam achievements and the inclusion of 'Episodes From Liberty City'. Whereas, an Intel Core 2 Quad Q6600 CPU or better is recommended. The GTA 4 PC requirements ask for a minimum CPU equivalent to an AMD Athlon 64 X2 TK-55. However, an NVIDIA GeForce 8600 GT or better is the recommended GPU. The minimum graphics card you need to run Grand Theft Auto 4 on is an ATI Radeon X1900. If possible, make sure your have 4 GB in order to meet the GTA IV requirements.
The minimum RAM requirement from Rockstar is 1GB, but your PC is likely to massively exceed this nowadays.
The GTA 4 system requirements ask for at least 16 GB free storage space.
