Just the power light is blinking on the router or just the power light is on R6300 Netgear router
It means firmware if corrupted on the router
u have update the firmware on the router on the router
Please follow this steps to Fix this problem,
Connect the modem to computer & follow this

Download the firmware from http://support.netgear.com/product/
The firmware will be in Zip format- un zip the file & select the CHK file
Download the TFTP utlity on the computer from this link- tinyurl.com/netgeartftp
Just save this file on the desktop
Connect the modem to router & computer
Assgin a static ip on lan adapter,right click on lan adapter & click on properties & click on Internet protocol TCP/ip & click on properties,select use the following ip address,of the router 192.168.1.2/192.168.1.1

Open the TFTP utlity,client type type the ip-192.168.1.1,password & select the CHK file- upgrade
it will tell firmware was successful updated.

U will see other lights on the router r coming on.
Release the static ip from lan adapter & u should be able to go online with the router

Nick.