Should You Purchase A Cable Modem?


I was paying my cable TV company nearly $5 a month to lease a broadband cable modem. Then, I realized I could buy my own, a purchase that would pay for itself in little over a year. So, I bought a Linksys CM100 from B&H, installed it myself, and returned the leased modem to RCN, the cable system operator. While owning your own modem makes sense for some cable customers, ownership isn't for everyone..

Swapping out one cable modem for another is straightforward. You transfer the coaxial cable and Ethernet wire from the leased modem to the new modem, then power up the new modem. Since the coaxial cable was already my active on-ramp to the Internet (the cable company is my Internet Service Provider or ISP) and the Ethernet wire already ran to my router for wired and wireless links to all the networked devices in my home, the physical set-up was complete.

When I launched the browser on my computer, I was automatically redirected to my cable company's site with a screen indicating that RCN had detected an unregistered modem. It prompted me to input account information. It stated that I would not be credited for the leased modem until I returned it. 

Front view with LEDs that indicate status Rear includes RJ-45 (yellow) and cable connections

I experienced some initial glitches. Download speed dropped from about 17-Megabits per second before switching modems to 7-Mbps.  Also, I was suddenly unable to connect to about half my bookmarked sites. So, I temporarily switched back to the leased modem. In a phone call with Linksys technical support, I was reassured that the modem was compatible. (I was replacing one made by Scientific-Atlanta, a Linksys sister company. Both are owned by Cisco.) So, I tried again, and this time, the data throughput was maintained, and I had no trouble accessing every site. After a few days of Net bliss, I returned the leased modem to RCN's walk-in store in Manhattan, where I was told I'd be credited $4 a month. It was a buck less than I expected, but the accrued savings would still be significant. The next month my bill did indeed decrease, a miracle in Cabletown.

If you're an RCN customer, the savings from investing in your own modem will come sooner than if you're a Time Warner Cable customer. TWC of NYC will shave $1 off your bill if you buy your own modem, which means you're looking at closer to five years to break even at current equipment and cable prices. Subscribers to CableVision's Optium Online service shouldn't expect any savings since the company says the modem is included with the service at no additional cost.

Then, there's the looking-forward question. While I don't expect cable companies to significantly increase download and upload speeds in the near future, there is a new standard coming called DOCSIS 3.0 which supports the type of  50 to 100-Mbps speeds experienced by Net users in places like South Korea. The CM100 as well as the D-Link DCM-202 (left) are DOCSIS 2.0-compatible but not 3.0-compatible.

So, if you think owning a cable modem will save you some money, check your cable company's Web site for a list of compatible models. And if you're not sure about how much you'll save, give your cable operator a call.

For more tips about  getting the most from your cable TV subscription, see 3 Ways to Get Your Money's Worth from Cable TV.


Do you carry any modesm for optimum online internet subscribers?

Or do you recommend any?

Hi Carlos - 

ARRIS TM822R XFINITY DOCSIS 3.0 Internet & Voice Modem 

  • DOCSIS 3.0 Cable Modem
  • Download Speeds up to 343 Mbps
  • 8 x Download Channels
  • 4 x Upload Channels
  • Dual VoIP Lines
  • 1 x Gigabit Ethernet Port
  • IPv4 & IPv6 Support

wish to purchase a modem that would allow me to watch TV, have you any suggestions

Cable modems may connect to the same coax cable that you receive your television signal on, but they do not allow you to watch TV, only connect to the internet.

Am trying to replace Toshiba PCX2500 cable modem.  Found one that is used.  Evidently Toshiba does not manufacture this one any more.  Is this a good buy for me at 16.00 + 6.00 shipping?

Thank you.

Hi Joann -

Given that this modem had cost about $80.00 to $100.00 when new - this seems like a good deal for you.

Please contact us via e-mail if you have additional questions:

What about those that have the phone line that goes into the cable modem box?  I haven't found a modem box that has this port as well.

The modems for purchase here are for those cable subscribers who get Internet or Internet and TV. Fo those subscribing to a triple play (TV, Internet, and phone), you're at the mercy of equipment leased to you from your cable company.

Remember that if you obtain internet, TV and phone from a cable provider, then this modem, without an RJ-11 or voice component is not an option -- unfortunately. 

Don't know if any modems that handle all three signals are available for sale.

Save yourself $30-$100.

Sign up on 'freecycle' a free giveaway site sponsered by  It's basically a huge free garage sale online.  You can 'ask' for stuff you need, and offer to take things listed as available.  There are always cable modems and DSL modems listed every week. If you don't see one in a day or two, go to the 'wanted' section and request one, you'll probably receive offers for a half dozen of them and pick the model compatible with your cable or phone system.

People are always moving or changing between DSL and Cable and throw these things in the closet and then want to get rid of them when someone plants the seed in their head. It's also environmentally responsible.

I used to think leasing was a good deal, in case something went wrong.  Then, while I was trying to reduce my cable bill, I realized I'd been paying $5 a month for a modem that was now over 6 years old.  That's $360 I paid to lease a trouble-free product.  I immediately bought an $80 DOCSIS 3.0-compliant modem.   At those rates, I could easily afford a spare, but I also found several modems on Craigslist for about $15 each.  So I don't reckon I'll be off to long, should it ever fail.

It is crazy not to buy your cable modem.  I bought one when I switched to cable 3 years ago on an install deal from Comcast.  After the rebate it cost me about $20.  I also bought one on CL for $10 for a spare.  OTH, I know of people that have had line surge issues and lost two or three in a year so they will only rent their modems.

I've been using the same Linksys cable modem for 3 years now. At $5/month for my area's lease fee, my modem paid for itself in about 15 months. When DOCSIS 3 is ready in my area, I'll be upgrading my modem and keeping the older DOCSIS 2 modem as a spare.

 Yeah me too on this one. I usually don;t like to lease but I decided to lease for now. I just got our of another situation where the Internet was down most of the time due to Poor Modems on a network. Right now all is well with Comcast

Granted that there will be no "leased fee" anymore but, remember that it's an "always on" concept so like a coffee maker that is "on" each and every moment, it'll wear out in time. You'll be lucky if it breaks down while still under warranty but there will be some down time. Should you just buy another one while you wait for repairs? At least with "leased" it'll get replaced no matter what. I just prefer a piece of mind...but that's just me!

You forgot to mention that Cisco will now allow the end user to upgrade firmware on cable modems. The cable company is responsaible for that and hesitate at best to do it. In my case they just won't. And that can cause troubles with new version of software like Windows 7.