Assuming off of what you have given us to work with, depending on your processor/projector and computer build itself all varies how smoothly and or nice it will look.
If you have a graphics card or motherboard that supports dual monitors and you are using dual monitors accordingly to manufacture's standards it should be ok depending on the speed of that graphics card.
If you have it all rendered as 1 video or it is 1 video it should be fine but will vary considering the frame size you have the video playing and rendered at.
As to the computer component issue you haven't left us with any details therefor we can much elaborate more than assuming. So if I by the off chance am wrong. Just know that no details were included so we could really diagnose this problem?
Well I sure hope I could help.