*Reposting this here as it is very relevant*
OK here im my experience using a "Marconi" modem
I have a AR800AM Ethernet ADSL router.
After hours and hours of scouring adsl sites and shops I found it based on what it looks like. These are in fact manufactured by an indian company called Dax Networks. Here is a link to the product on their site.
http://www.apcomgroup.com/Dax/Products/Router/DaxADSL.htm
As you can see(If you have one) the modem is identical. I got them to email me the user manual and that is identical as well. It is in fact the same modem. It is also, in fact, a total peice of crap.
I decided to get a ethernet router/modem for ease of use and installation. These things are supposed to do NAT for you and handle all the dialup stuff. The telkom guys dumped it here and tested it using a "dialup connection" from their laptop and verified that everything was fine. In fact what they did was use the modem as a PPPoE device (PPP over ethernet). After spending some time with the support people on the phone I realised they had no clue as to how to set it up other than as a dial up device so I went about setting it up myself. The reason I got an ethernet modem was because I wanted it to route and dial for me not so that I could pay more.
Once set up the modem seemed to work ok, albiet that it had obscure terms like PAT for the NAT set up. Problem is it kept on crashing, and I had to keep rebooting it every now and again. Started crashing after about 18 hours and then every few hours after that. I noticed that the device got very hot so I assumed something was wrong with it and had telkom swap it out. (PS it does not handle LCP ip change requests very well, this is what telkom uses to cycle your ip)
My new modem had the same problem. Eventually I decided to hook it up to my linux machine and use it as a PPPoE device. The modem ran a lot cooler and has not given me a problem since.
In conclusion.
<ul><li>This router is broken (by design)</li>
<li>It should not be used as a router but as a modem. (as telkom seems to want you to use it)</li>
<li>If used as a router (the reason you pay for it) it overheats and crashes.</li>
<li>If used as a router it does not handle LCP(line control protocol) requests well and crashes.</li>
<li>If you need a router/modem solution get something else. Otherwise just get a cheaper USB version.</li>
<li>Ripped off again, thank you Telkom.</li></ul>
]
]