switch v. hubs

do to an excessive number of grand-kids I had to add a computer to my network, and i was using a Netgear 10/100 5 port switch with 2 computers, after adding a computer, only 2 computers at a time can find internet, what should I add/change to make all find internet I am using cable supplied modem
and I need an aspirin please n thanks ppl :-D

 

Sounds like you need to do a hard reset of the modem if still powered when machine #3 was connected.
Power down all PCs, unplug the power to your modem for about a minute.
Power up the modem. When all lights are burning, power up the PCs.

 

Sounds like your trying to get dhcp from your modem which may not work depending on how many ips your isp will give you, Best bet is to buy a router to handle the dhcp and such on your end. If you do a ipconfig and tell me the ip of the two machines that actually do work, we can determine if your cable modem is handing out private internal ips, or just handing out two wan ips to the different computers from your isp.

 

I have tried all the obvious things, different cables, different ports, , , and the shut it all down and restart cable modem , and it still only lets 2 computers on at a time, SO NOW I am going to try Colemanguys theory have 8 coleman lanterns and two stoves, , , :confused have to many shells, , , maybe i can use them for mulch?

 

Two computers at any time, espcialy if its the first two computers to come on indicates that your isp is just giving you two dhcp addresses. A simple ipconfig will tell us if your machine is getting a public ip from your isp, or if you modem is doing dhcp and not set for more then two ips or something with it is the issue.

 

as stated in ordinal post am using a cable modem and ethernet switch (NetGear) and yes is it only letting the first two computers powered up to log in, did a ipconfig, which tells me on the XP macine an IP address, on second machine is Win 7 and didn't display a IP address so I guess I need a router in stead of switch? or different modem? the crack s are getting worse rolleyes

 

A good router should do it.