The most reliable version for on PC is Patch 1.6.0 , which specifically addresses critical stability and performance issues. If you are looking for information on a "hotfix repack," it likely refers to the secondary update Ubisoft released to fix a major save-game bug introduced by the original 1.6.0 patch. Patch 1.6.0 & Hotfix Key Features
The hotfix included in many 1.6 repack updates contains a modified .dll or executable that forces the game to bypass these hardware checks, allowing players with older or mid-range systems to enjoy the game without a hitch. How to Apply the Patch to Your Repack far cry 4 patch 16 hotfix repack