Conga Composer can merge data into a Microsoft PowerPoint PPTX template.
What Exactly is a PowerPoint PPTX Template?
It is a PowerPoint file (.pptx), created in PowerPoint 2007 or PowerPoint 2010, which contains one or more merge fields.
Conga Composer release 8 does not support PowerPoint 2003 (.ppt) templates. You must use PowerPoint 2007 or later (.pptx).
The Template Builder is an essential tool in the development of Conga Composer solutions. The Template Builder exposes the data retrieved by Conga Composer from the Master Object (and from any Salesforce Reports or Conga Queries referenced in the Conga Composer URL). You can then us these fields to build templates.