Recs.
Updated
OBS (Open BroadcasterSoftware) is a free and open source screen recorder written in C / C++ that also supports livestreams and webcams.
SpecsUpdate
Pros
Pro Plugins friendly
OBS has over 20 plugins to choose from, including one's that allow adding video files and any other media supported by VLC as a source, integrating Twich chat and switching scene depending on what window is in focus. OBS has an API allowing developers to create their own unique plugins, giving them and others complete control of their streaming experience.
Pro Supports Intel's Quick Sync for faster and more power efficient video processing
Quick Sync is hardware video encoding and decoding technology that's comparable in speed, compression ratio and quality to x264. Since Quick Sync is a dedicated hardware core on the processor die, it allows for faster and more power efficient video processing.