Did you set the frame rate of the composition to a custom value or is it still at auto?
Also keep in mind that in video, more fps is not necessarily better (as many gamers would think!).
For example: the movies you watch in the cinema are all 24fps.
low fps
Re: low fps
Sounds like you have your GUI monitor to the onboard GPU, then usually this GPU is doing all the work, can you try if you see better performance if you connect your monitor to one of the outputs of the A5000?