wireless access point using Motorola SBG6580 Cable Modem as secondary

I replaced my Motorola Surfboard SBG6580 cable modem with a Zoom cable modem and would like to use the SBG6580 in our upstairs as a wireless access point since I have trouble with wireless coverage up there.

My current setup is my Zoom cable Modem downstairs has the comcast incoming cable and an ethernet cable out to an ASUS RT-N66U 450Mbps Dual N Band Router. The bedroom upstairs has a hardwired CAT5 connection that is plugged into the ASUS Router. Our son just moved out so there is no computer up there now and I would like to connect the SBG6580 in there. My main computer downstairs is also connected to the ASUS router.

I have done a reset of the SBG6580 and plugged it in upstairs and connected it to the ethernet connection. However, when I come downstairs to my computer and type the ip address into my Chrome browser, I am unable to access the settings on the router. It says page not found.

My question is do I have to disconnect the Zoom Cable modem from the Comcast connection and reconnect it to the SBG6580 (secondary modem)? Do I also then need to connect my computer via ethernet to the SBG6580 in order to reconfigure the SBG6580 as an access point?

Attempting this is a real stretch for me - I am not a computer geek. My head is spinning - can you help please? Thank you!

Elaine

Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 8.1 Pro, 64 bit
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