Complex sentence: Some third party hard disks for IBM PCs were sold as kits including a controller card and replacement power supply, and some were integrated with their controller into a single expansion card, commonly called a "Hard Card".
Split into simpler sentences: Some third party hard disks for IBM PCs were sold as kits including a controller card and replacement power supply. Finally, some hard disks were integrated with their controller into a single expansion card, commonly called a "Hard Card".