I've been using an Arris SURFboard SB8200 modem with the paired gateway/router setup for about two years. Over the past month or two, the router has repeatedly started blinking white and rebooting on its own. Sometimes it recovers after 10 minutes, while other times the outage lasts up to two hours, and this can happen several times a day. My modem itself remains stable with no internet connection problems. A PC, Xbox Series X, and two smart TVs are connected to the network. I've already unplugged both devices, waited, restarted them in the correct order, swapped the two routers, checked traffic-priority settings, and confirmed that I'm using the original cables. Is there anything else I can try, such as a firmware update, factory reset, cooling check, or power-adapter test, or is the router probably failing and due for replacement?
2 Answers
Since the modem stays online and you’ve already swapped the routers and checked the basic connections, this points more toward a router hardware or power problem than an ISP issue. Check that the router is well ventilated, isn’t unusually hot, and is connected directly to a reliable outlet. If possible, test it with another compatible power adapter that has the exact same voltage, polarity, and equal or higher amperage. Also check the manufacturer’s app or admin page for firmware updates and logs showing why it is rebooting. A factory reset is worth trying after backing up your settings, but repeated power cycles usually mean the router or its power supply is failing.
I’d also temporarily disconnect every device except one computer and watch the router. If it still reboots with almost nothing connected, the connected devices and traffic settings probably aren’t the cause. If the problem began after a firmware update or configuration change, reset it and set it up from scratch rather than restoring an old backup. If it continues after that, replacement is likely the practical fix—two years isn’t especially old, but consumer networking hardware and its power bricks can fail earlier than expected.

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