My recommendations:
(1) If you are beginning cable modem service, do not purchase a modem yet. Pay the $10 rental per month for a couple months to make sure everything is fully operational — make sure any problem is the cable provider’s problem. Don’t forget that the cable ISP may offer a referral reward program (e.g. a free month for the person referring you) — check
with a friend and make sure someone gets credit BEFORE YOU SIGN UP.
(2) If you do not have an Ethernet network adapter built into your computer, or already have an Ethernet card in it, you will need either an Ethernet card or an Ethernet USB adapter. I suggest the Ethernet PCI card for a desktop and the Ethernet "cardbus" PC Card for notebooks.
(3) Call your cable Internet service provider to make sure you know what belongs to you and what you have to return — do you own the network interface card or the USB network adapter that they installed, or do you have to return it and buy a corresponding item.
(4) If you’ve been renting a cable modem for a while, and your connection is reliable, buy one.
(5) Consider the Toshiba PCX-1100U. I liked it, and you should, too. [2003 -- the PCX-1100U has been replaced by later models. Don't waste time trying to find it. I recommend Linksys networking products.]
(6) Take the rental unit back and cut your costs $10/month.
h2>2005 Update:
I now recommend the Motorola Surfboard SB5100. One of its nice features is a built-in web server at 192.168.1.100. This web server doesn’t let you access or provide web pages to the public. It provides diagnostic information to you on how well the modem is working.
h2>2010 Update:
I’ve updated my modem as my cable company’s system has gotten more powerful. I use and recommend the Motorola Surfboard SB6120, which is built to be DOCSIS 3.0 compliant. It also has the built-in web server at 192.168.1.100. This webserver doesn’t let you access or provide webpages to the public. It provides diagnostic information to you on how well the modem is working.
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