Hi, hoping someone can help me with this issue.
I just bought an ASUS RT-N16 router to replace my netgear DG834N; so far it is working much better as far as wireless signal goes. Of course the RT-N16 comes without an ADSL modem so I bought the Draytek Vigor 120 to go with it.
My internet connection is working as the DG834N connects just fine. But the Vigor 120 wouldn't connect. I wired it up directly to my laptop to check what it was doing and all the settings (PPPoA etc.) are exactly the same as on the DG834N, since I'm with BT and they use standard settings. The Vigor 120 even connects to the ADSL line, finds my upstream and downstream connection speeds, and the DSL status says "SHOWTIME" (whatever that means). But the "internet" light on the modem stays OFF and I can't ping any external IP addresses; not the DNS, not the gateway, nothing. From what I've read it should just work when you plug it in so I'm at a loss as to what to do. I suspect the unit may be faulty, but there could be something I need to do in order to set it up that I've overlooked.

You are making good progress.
Don't expect the internet LED to ever light up.
SHOWTIME is excellent news.

Connect the Ethernet Cable Between your Draytek Vigor 120 and the "internet" single Ethernet socket on your new ASUS RT-N16.

Log in to the settings on the ASUS, and put Internet Connection to PPPoE and in here you put in your internet connection username and password.

e.g.
broadbanduser@btinternet.com

(I understand that BT connections don't require a password).

You should see these on the Basic Settings page on your Netgear if you need to confirm.

Regards, Neal

Hi Neal,
I tried what you said. I'm running DD-WRT firmware on the RT-N16 router. Unfortunately it just won't connect - in the WAN status page it just says "disconnected" as though it can't even find the modem. I can't access the modem through its IP 192.168.2.1. The only way I can get the router to connect is by setting a static IP, but then I'm not sure if it's really connected as I still can't access the internet or the modem. The only way to access the modem is to connect it directly to my computer, and to not use DHCP, instead setting a manual IP address. I can see the "SHOWTIME" when I log into the modem but I cannot connect to the internet at all.
As I have it set up at the moment, I am using my old router to connect to the internet and I set my new router in its DMZ. This is the only way I could get it to work.
I am probably going to ask for a replacement for the Vigor 120.

What happens if you follow the "Windows XP PPPoE Setup" section of http://www.draytek.co.uk/support/kb_vigor100_setup.html ?

Make sure you've left the "service name" setting blank, which is required because of the way the PPPoE passthru works.