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Networking problem

  1. Aug 2, 2005 #1
    I have an Acer Aspire 3000 and it has a SiS 900-based PCI Fast Ethernet Adapter. My problem is that no matter how I try to connect the laptop to another desktop computer or to a cable-dsl modem it tells me that there is limited or no connectivity. When I try to repair it it says that the IP is not being reassigned. I used the normal cat5 ethernet cable. When I do ipconfig /release on the laptop dhcp is enabled and everthing else seems to be normal. All the settings for TCP/IP, etc. is set to automatic.

    Does anyone have a clue as to what may be causing this?
  2. jcsd
  3. Aug 2, 2005 #2


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    Staff: Mentor

    If you aren't connecting to a router (a router's job is to assign/manage ip addresses), you need to assign it an ip address manually. However, I thought cable modems had router functionality (for one pc)...

    If you are connecting directly between the pc and the laptop, you need a crossover cable and to assign ip addresses for both.
  4. Aug 2, 2005 #3
    the thing is when i connect the desktop computer to the cable modem it works (this is the connection that I am using now), but when i connect the laptop to the desktop or the laptop to the desktop i get limited or no connectivity.
  5. Aug 2, 2005 #4
    i noticed that the adapter at the back of the desktop has only four pins but my laptop has all 8, i don't know if that makes a difference (for e.g. if i need a different kind of cable or something)
  6. Aug 2, 2005 #5


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    Staff Emeritus

    If your connecting the laptop directly to the desktop then you need a crossover cable. If you connecting the laptop to the router which is connected to the desktop, then you can use regular ethernet.

    Instead of relying on the dhcp server, why don't you give the laptop a static ip. You'll need 3 pieces of information (5 if you want the laptop to have internet access):

    I'm assuming your router's gateway address is One way to check this is to go to your browser and type that address. You should get a login window.

    IP Address(you want the laptop to have): 192.168.1.[2-255]
    Gateway Address:
    DNS1: You can get this from your router if your connected to broadband. Ignore if you don't.
    DNS2: You can get this from your router if your connected to broadband. Ignore if you don't.

    I forgot where you put this in windows, but in linux the dns info goes into /etc/resolv.conf and the rest goes in /etc/conf.d/net.
    Last edited: Aug 2, 2005
  7. Aug 2, 2005 #6


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    Staff: Mentor

    Right, like I (and dduardo) said, you need a crossover cable.
    Four pins is a phone line and an ethernet cable won't fit in it...
  8. Aug 2, 2005 #7
    guys i know what a crossover cable is, and what a straight cable is. I have to check to see which one i have at the moment since i have not done so yet. I have a feeling that the problem is with the cable because packets are being sent out, but none are coming in.

    the ethernet card in the desktop computer has four pins in its card (pci) and uses an ordinary rj45 plug.
    Last edited: Aug 2, 2005
  9. Aug 3, 2005 #8
    Finally I got this thing to work. Over the past two days I was really pissed because I was not getting it to to work. Also guess what, the problem was not with the cable or the modem or anything else EXCEPT windows xp. It was only last night that I learned that there was some problem with winsock, dhcp in sp2. so i got a couple fixes off the net and finally got it to work. It was lastnight that i realised the pain that alot of people went through too. the reason I was not aware of this is because only last week i moved to dsl from dialup.

    windows cost me another two days
  10. Aug 12, 2005 #9
    yea windows is frustrating to use with networks. You sound like a linux guy. And whats the sp2 in dhcp?
  11. Aug 17, 2005 #10
    it is DHCP in SP2. DHCP stands for Dynamic Host Configuration Protocol, and it is responsible for assigning an ip address to a computer. SP2 is service pack 2.
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