: It achieves high performance through a rapid gradient-optimization conformational search, which works in tandem with the multi-core execution to provide results much faster than older docking engines. Read the Docs step-by-step guide

AutoDock_Vina_1_1_2.tar.gz...

This is the primary official source.

: You can't just use standard .pdb files. Everything must be converted to the .pdbqt format before Vina can read it.

No. Use AutoDock Tools (ADT) or the free program (which includes Vina 1.1.2 internally) for a graphical interface. But for standalone download, only CLI.

The official repository for the source code and latest releases.