Readynas NV+ RND4000 installing drives

I have a Readynas NV+ RND4000 in our SMB and as of yesterday started having a problem. After troubleshooting I found that it will freeze when accessing the files, unplug the ethernet cable, plug back in and it's accessible again for maybe a minute. Then repeat unplugging and plugging back in. I replaced the cable and switch and problem still exists. Did the OS Re-install, problem still exists. I have determined that this must be a hardware issue (failing nic?) and found a new NV+ online.

My question is, I plan on installing my existing drives in the new NV+ and booting it up. I then expect to have to go to setup via raidar and change the ip and any other settings to match the old unit. Is there anything more than this? I can NOT lose the data on the existing drives. That is really my only fear.

Will this work as I expect? And if you have any thoughts on the failure, I'd love ideas.

Also, I called Netgear yesterday and paid the $75 for help. They basically suggested doing the OS Re-install...nothing else. Truly a waste of $75.

Thanks,

Landon