Kk I had the same problem on my HP envy m6, I used to only be able to see my cursor. What you may want to try, since there is two video adapter on a laptop (one for high performance and one for when on the battery from what I understood), you need to change your performance settings. To do that I simply right clicked the battery icon at the bottom right of my screen, went into ''power supply options'' and went into advanced settings. There I was able to choose how much performance I could draw into different aspect of the PC such as Hard drive, processor and graphic settings. By playing around with Graphics setting (minimizing it or maximizing) you might be able to get the right video adapter to work with OBS. For me I put my laptop on high performance settings and I maximized the graphic settings and it worked.
I hope this can help some people, tell me if it also worked for you.
On windows 8.1 btw and my graphic card is a radeon card
