Do two NVS810 cards in single window 8 system support 3x5 1080p display?

We have a data visualization web app, with several svg based charts and several real time h5 video sections in the same page. Now we want to project the output to 3x5 1080p display, we have two NVS810 cards installed in a windows8 dell workstation, we found the page rendered slow, videos played are not smooth. Do we have the right choice for the solution? If not, what is the suggestion?

Thanks!

Not sure if you have solved this issue or not, but I have built a 15 panel 3x5 video wall using two NVS 810s and it functions properly, with smooth images and content across the whole surface.