This might sound like a stupid question, but when I'm upgrading my pre-built computers, I always have to remove a pre-installed PCI (or PCI-E x1) modem to make room for other parts. So I'm wondering - what are all the possible uses of having a modem installed in a machine? There seems to be one and two port variants - what are the differences?

5 Answers 5


Modems are an old item that still remains in lots of current pc's.
1. You have 2 ports, 1 to connect the telephone LINE and one to connect your telephone to
2.I have used them for lots of appliations in the past

  • fax machine
  • answering machine
  • phone-call recording device
  • the obvius internet connectivity thingie
  • connect 2 pc's in a place where you only have a local PBX between the 2 places but no way to get ethernet passed (in one wierd sittuation it was quite ok
  • also modems were very common in laptops untill 1 year or so ago... reasons unknown
  • 2
    • 2
      Some of that uses are still current in some parts of the world!
      – AndrejaKo
      Jan 9, 2011 at 10:37
    • used it once on my old laptop to get connected via a VPN connection to our offices, it's painfully slow to be tied to a modem but it get's the work done. 10x god for terminal connection :) a lot less overhead then gui.
      – user13834
      Jan 9, 2011 at 20:11

    What model are you talking about ?
    Usually it just has port for you phone jack from the dial-up era .
    Any way if you have not been plugging anything in your modem I don't think there should be any problem removing it.


    A PCI card dial-up modem is -very- useful. If your NAT router is down, you can use that to get online.

    In the UK, it's PAYG, cost of a phone call, and there are a few providers, so you can always just use dial up without being reliant on any one provider. So if one has a problem, others can work, so it is very reliable in an emergency. You may not have that advantage in the USA. That's the main use nowadays.

    Dial-up isn't that secure like being behind a Cable/DSL NAT Router.
    (most people just connected one computer to the wall, though maybe some had NAT Routers, I don't know)

    There are DSL modems too. But quite rare. They just connect one computer to the wall, and they don't do NAT.

    • I wrote "There are DSL modems too. But quite rare. They just connect one computer to the wall, and they don't do NAT." <-- I don't think I've seen one, I have seen a device with only one port for a computer and one for the telephone line, it had a modem and was advertised as a dsl modem, it did do NAT but you could put it into bridge mode which also turns off NAT. Many NAT routers can be put into bridge mode, turning off the routing functionality. They typically have a switch in there providing many LAN ports but some can be one LAN port.
      – barlop
      Aug 6, 2015 at 10:12

    Once upon a time, in a land before 'broadband' was a word most people had heard of before, and modems connected to either serial ports or ISA slots, there were different versions of end-user modems. These days everything is a Hayes command-set modem. Their original use has largely gone by the way-side, though there are still some blighted corners where dial-up is still the only reliable internet access method. They still remain useful for that last bastion of analog inter-machine communication: Faxing.

    You can do other things with them depending on the software you have. For instance, you can monitor Caller-ID information.


    These days I still use a couple of dial-up modems. One for my HTPC, where the caller's name/number appears on the television, and the other one in my main desktop machine, for dialling out from my Outlook contact list. They are 'winmodems', which are inbetween soft and full hardware modems and getting Windows x64 drivers was pretty difficult.

    You must log in to answer this question.

    Not the answer you're looking for? Browse other questions tagged .