Hi , you need internet to be able to view your 7 DVR(s) remotely , assuming your branches are a bit far from control room . in this case im using an android to view (similarly yours) my store branches . if you want each branch per monitor you need 1 cpu for each monitor. i hope it helps
PS. I use Yudor, Dlink, Longse DVR
I view them all together using IP Cam Viewer Pro
to run IP Cam Viewer Pro on PC you need bluestacks