netgear CM1000 MODEM-Nighthawk R7800 router losing wifi signal

we have a quad level home, 2500 sqft .we just upgraded our cable to 600mbps so we upgraded our modem to a netgear cm1000. we have a netgear R7800 nighthawk router. they are on the second level with the modem, tv, and roku box. they are all about 8 ft. apart from each other. we have 2 desktops, 2 laptops, roku, a wireless ADT alarm system w/ doorbell camera, 2 motion sensors, 2 smoke detectors, 2 carbon detectors, with that being said, the router drops signal half dozen times or better /week. do I need to upgrade the router ?