Some players preferred "downgrading" to Patch 1.0.4.0 because it offered better performance and shadow rendering on older hardware, whereas 1.0.8.0 was a minor late-stage update.
Rockstar Games released several major official patches to address crashes, graphics rendering, and multiplayer connectivity: GTA IV Patch
Fixing the "Out of Video Memory" errors that prevented players from using high-resolution textures on modern GPUs. Some players preferred "downgrading" to Patch 1