This note is at the bottom of the PowerDirector 11 product web page on the Spec tab:
"1. Accelerated video encoding on AMD graphics cards requires the user to install the AMD Media Codec Package, also known as the Avivo™ Package. This package is available as an optional download when obtaining an AMD Catalyst™ Display Driver for AMD desktop graphics and notebook graphics products, available at www.amd.com."
After searching the AMD website, I got to the following page where I had to fill out a form after which I could download the codec package.
http://support.amd.com/us/gpudownload/windows/Pages/eyespeed_downloads.aspx
After installing the codecs, the "Fast video rendering technology" and "Hardware video encoder" options became enabled on my computer for MPEG-2, h.264/AVC, WMV, MPEG-4, and MKV formats. Gateway DX4380, AMD A8-5500 Quad Core 3.2GHz with ATI Radeon HD 7560D; 16GB RAM; 1 TB SATA 7200 RPM; Windows 8 Pro 64-bit; PDR11, PDVD12.