Are you looking for the best modem for Comcast? Checkout the very excellent Motorola SB6121 Cable Modem. It is approved for Comcast.

1. The Motorola SB6121 Cable
Modem Is The Best Modem
For Comcast
By Rafael Ariannete
If you are looking for the best modem for Comcast, you don’t have to go any further than the
excellent Motorola SB6121 cable modem.
These are the features that make the Motorola SB6121 the best modem for Comcast:
Listed on the approved modem list of Comcast
Highest (3 stars) Comcast rated modem
DOCSIS 3.0-certified (EuroDOCSIS 3.0-based)
Channel bonding of up to 4 downstream and 4 upstream channels
1 GHz capable tuners
Supports IPv4 and IPv6 to expand network addressing capabilities Compatible with
Windows, Macintosh, and UNIX computers.
Gigabit Ethernet (RJ-45) data port enable flexible, high-speed connectivity with Auto
Negotiate and Auto MDIX
Plug and play installation
Front panel LEDs indicate status and simplify troubleshooting
Multi-language user guides
Supports standard internet software
User-friendly online diagnostics
Just to make sure that you are making the right decision to invest in the best modem for
Comcast that is available in the market today, here are some owners of the SB6121 sharing
their experience with you:
Motorola SB6121: Great Modem works with Comcast, June 29, 2011
By Falcon (Texas, USA)
Bottom line: the Motorola SB6121 is a great modem and it works with Comcast.
Comcast just doesn't have its act together. This modem is not only on their approved list, it
has a three star rating, which, according to Comcast, is "the highest and most thorough
level of testing." When the cable installer got here (I got a new line installed), he said that
this modem was NOT on the Comcast list.
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2. Since I still had my DSL line working, I showed him that not only did Comcast approve the
modem but that Comcast thoroughly tested it. He had to call the "office" to activate the
internet service. The "office" didn't want to set up internet service for this modem; the
"office" stated that this wasn't an approved modem. Well, he recalled the "office" and got
someone else and they set up the service.
I've been happy ever since. I'm supposed to get up to 20 Mbps download and 4 Mbps
upload. My computers are connected wirelessly. Speednet states that I am getting 20 to 25
Mbps downloads and the upload speed is between 3 and 3.5 Mbps. I've gotten similar
values with speakeasy and other internet speed testing sites. I have a lot of devices
connected: three computers (wireless), two TVs (one wired, one wireless), three different
game consoles (connected to the wired TV), two Nintendo 3DS (wireless), one printer
(wireless), and an iPod Touch (wireless). At times all of these devices are running at the
same time - the computers are streaming You Tube videos, one of the TVs is streaming
Netflix, etc. The modem handles all of it effortlessly. I'm really pleased with this modem.
I find this to be the best modem for Comcast.
Works and Easy Comcast Self Hookup, December 14, 2011
By RightReviewNow
12/14/2011 Just received the Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem
today. Followed the self-install instructions included with the modem, using Comcast
internet, and a Medialink Wireless N router, and was up and running in 20 minutes. Note;
also used a Windows OS laptop for the setup, with Internet Explorer.
Here's how my setup went. Disconnect your old modem. Connect the SB6121 modem to
your internet coaxle cable. Now connect the ethernet cable to both the SB6121 modem and
your computer. Power up the SB6121 modem and wait for all lights to stop flashing (must
have solid lights), then power up your computer. Now, open Internet Explorer browser and
wait for the Xfinity screen to automatically show up on your Internet Explorer's screen.
Enter your Comcast account number and the phone number associated with your Comcast
account on the screen, where asked, and press next. The SB6121 modem will then be
automatically identified and recognized.
Press next to accept the Motorola SB6121 cable modem, then wait a few minutes for the
next screen to show up while the information is being processed, then press finished. 3
screens total. Disconnect the ethernet cable from your computer and connect it to your
router. Now, power both the SB6121 and your router off and wait 10 seconds.
Now, power the SB6121 modem on and wait for all the lights to show themselves. Now,
power on your router. You should be able to go online wirelessly. Literally that simple. The
Comcast Xfinity self-install screens did not ask me for a MAC address or a serial number.
Total time - about 20 minutes to remove the old modem and install the SB6121. Best part,
no having to call tech support and no frustration!
I was quite surprised at how easy the SB6121 was to install, as it seems like I'm one of
those guys who takes 2-3 hours to hook anything up. Seems like there's always that one
thing I didn't know, or think, about, and I'm usually on the phone with tech support for a
while having a lackluster time. I replaced an old Comcast RCA modem which I had no
problems with, but was tired of renting from Comcast at $84 per year. The SB6121 will pay
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3. for itself in a year's time, is a 3 docsis modem versus 2 on my old modem, and works well
thus far.
Awesome speeds, June 2, 2011
By Voidedsoul
Don't listen to the people saying this wont work with Comcast. It is now on their list of
approved modems and it works great. I'm paying for 15 Mbs and hitting 20 on a regular
basis on speedtest.net. Great product totally worth it. Also my 20 Mbs is over wireless
haven't tried it wired, it may be even faster.
Fast speeds and reliable Internet with Comcast, January 7, 2012
By Romy
ISP: Comcast
Comcast Internet Package: Performance ( 15 Mbps )
Comcast provided modem: Their "latest DOCSIS 3.0 Arris" modem
Router: Linksys E4200 v1
The reason why I bought this modem was simple...why pay $7/month to rent a modem
when I can buy one myself, with potentially better specs, and cost savings 10 months out. I
found good reviews for this modem and figured why not, especially since
http://mydeviceinfo.comcast.net/ shows that this specific modem is signed off as supported
by Comcast, along with their highest, 3-star rating.
I can't be certain that the new Motorola modem is buying me speed/reliability over the Arris
modem, but I know that my wife and I have been running our computers and game
consoles without a hitch. With the Arris modem, we found the internet to slow down several
times a week requiring modem reboots, but maybe we're just getting lucky. But hey,
possible positives are a good thing right?
I'm paying for Comcast's performance package which claims speeds of 15 Mbps down. With
the Arris I was seeing speeds around ~17-25 Mbps down. With the Motorola SB6121 I'm
seeing 20-25 Mbps down ( both much higher than expected ).I've seen slow uploads
with both modems, but I think that's a Comcast thing. ( random: I previously had FiOS
25/25 and was getting 30/25. those were the good ol' days )
If you're using this with Comcast, remember that you're going to have to contact customer
service and get them to send a signal to your new modem in order for it to work - don't
expect it to be plug-n-play.
Great Modem - Perfect with Comcast, December 28, 2011
By T. Kendall
This is much better than paying Comcast $7 a month to "rent" their modem. It was 100%
Plug and Play instead of "Plug and Pray", as many are. Works great and is so much faster
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4. than current Comcast or any cable service, it should be a viable device for many years
and a good investment.
WORKS WITH COMCAST - Northern California, July 6, 2011
By Amazonian "Michael R." (San Rafael, CA)
Great Modem.Super fast.hooked up in about 15 minutes. Had to call Comcast and was able
to get things activated through online chat. Also works great with my Apple Airport Extreme
Base Station with my Vonage Router -- Bridged(off). Vonage was the only Hiccup of the
process. Needed to unhook my Vonage router so my SB6121 could be recognized by
Comcast, THEN hook back up Vonage, reset it and go.
I'm hitting a SOLID 35.95 Mbps with 6.50 Upload. Wireless! -- Very Happy.
The best modem for Comcast
If you are looking for the best modem for Comcast, then you should look no further than the
Motorola SB6121. In summary, with the Motorola SB6121 you get:
Comcast approved and highest rated cable modem
Better specs than modem supplied by Comcast?
Savings as you do not need to pay the monthly rental anymore
Superfast upload and download speeds
Easy to install modem
DOCSIS 3.0 Certified – so you are future proof and your investment is protected
Elegant Modem casing that fits nicely anywhere in your house or office
With so many happy owners replacing their rented modem with the Motorola SB6121, it could
be very easily voted as the best modem for Comcast.
Click here to buy SB6121 at one of the best discounts available today.
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