Ratings and Reviews
Shop Now At Walmart

Customer Reviews for Motorola ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Motorola ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

The Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem unlocks the potential of offering innovative high-bandwidth data and multimedia services. Utilizing the power of DOCSIS 3.0, the SB6121 enables channel bonding of up to four downstream channels and four upstream channels, which allows an operator to offer their customers advanced multimedia services with data rates of well over 100Mbps in each direction. The Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem provides an economic option for providing Ultra-Broadband services, with four times the current maximum user data throughput approximating 160Mbps in DOCSIS mode and 195Mbps in EuroDOCSIS mode, without the need for hybrid fiber coax (HFC) plant upgrade. Maximizing an operator's current infrastructure investment, the SB6121 can be deployed without service interruption.
Average Customer Rating:
4.606 out of 5
4.6
 out of 
5
(602 Reviews) 530
Open Ratings Snapshot
Rating SnapshotOverall Rating Totals
5 stars
448
4 stars
116
3 stars
14
2 stars
3
1 star
21
Customer Recommendation96%577 out of 602reviewers would recommend this product to a friend.
Customer Questions & Answers:
113 Questions | 397 Answers
Open Ratings Snapshot
Rating SnapshotOverall Rating Totals
5 stars
448
4 stars
116
3 stars
14
2 stars
3
1 star
21
Customer Reviews
Review 1 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Easy to hook up

04/27/2014
By
5 out of 5
5 out of 5
Works great with my Cox high speed internet connection.
Click an image to enlarge it.
User submitted photo
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:55 - 64
Gender:Male
Ownership:2 - 7 weeks
Usage:Every day
+18points
Thank you! You have successfully submitted a comment for this review.
Read Comments (2)
Read Comments (2)
Customer Avatar
arizona
comcast
Posted 09/26/2014
will my comcast on my tv work with this ?
0points
Customer Avatar
Florida
SB6121
Posted 09/26/2014
I decide, I was going to stop renting a modem. I looked at several, I like the reviews on this one, I purchased it online.
The online experience was great. The modem powered up configured and I'm up and running.
0points
Read Comments (2)
Read Comments (2)
Review 2 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Just right for home use. Stop paying rental fees.

02/20/2014
By ,
Los Angeles, CA
5 out of 5
5 out of 5
When I learned I was paying Time Warner Cable $7 a month for a DOCSIS 2.0 modem (no longer in use) for many years and could purchase my own - I did. I followed the "where to plug in the three cables" instructions (cable company line, ethernet line to router and power line). With my computer and modem on, I called "TWC technical support" to give them the MAC ID number on the side of the unit. The TWC rep "set up" my new modem and removed the monthly charge. The entire process of hooking it up and finishing with TWC was less than ten minutes. I took longer to hide the new power cable behind my desk.
Ordering online is a few bucks cheaper than purchasing in the store (and cheaper than Best Buy, Office Depot and Frys). My Walmart is a few blocks away so I had mine shipped to the store. They emailed me when the modem arrived. Walmart has a special line for "ship to store" pickups - so no waiting in the "merchandise returns" line.
I will never pay a monthly modem fee again. So far, so good. Thank you Walmart.
Recommends this product? Yes
Age:55 - 64
Gender:Male
Ownership:2 - 7 weeks
Usage:Every day
+104points
Thank you! You have successfully submitted a comment for this review.
Review 3 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Does the job well, for a good price.

10/19/2013
By ,
Salem, OR
4 out of 5
4 out of 5
This is my second purchase of this model. First one 6 months ago is at home and this one at my son's college house. Both needed to be Comcast compatible and DOCSIS 3.0 to be future proof. They are fast, and easy to set up after the required call to Comcast support to allow them on their network. My only complaint with the modems is every once in a while they trip off and restart for no reason. I have not researched this issue yet, because it is very brief, albeit annoying.
Another complaint is with Walmart's stock reporting system. My second one's online purchase confirmed in stock status, but none was at the store when I arrived, the out of stock text came while I was leaving the parking lot. So, I cancelled that purchase and ordered it from a store near my son's house, which also showed it in stock, but a text came saying it was on back order a few days. There is definitely a problem with Walmart's stock inventory network and its communication with their online store.
Product Attributes:
Value
4 out of 5
4 out of 5
Meets Expectations
4 out of 5
4 out of 5
Recommends this product? Yes
Age:45 - 54
Gender:Male
Ownership:2 - 7 weeks
Usage:Every day
+40points
Thank you! You have successfully submitted a comment for this review.
Review 4 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Excellent modem for the price!

10/29/2013
By ,
Brunswick, OH
5 out of 5
5 out of 5
I decided to purchase this modem after our previous Motorola SB5100 began having sync issue. After spending nearly an hour troubleshooting our connection issue with cable provider, I was offered a replacement through them at a monthly lease charge of $6.99 a month. For that amount I justified the cost of this replacement and avoiding the monthly charge. Setup of the Motorola SB6121 was easy and straight forward. A 10 minute phone call to cable tech support to switch out the equipment and we were back up and running. Our internet connection is a 30x5 we were averaging 19x1 with the old modem. We now are getting 30x4.3. The added feature of the multi-speed Ethernet port is nice. If your Router WAN Port is Gigabit capable, the lag when connecting and downloading is gone. The modem is great for those who stream video, music, and online game. It also resolved a lag issue when streaming content from our DirecTV dvr.
Product Attributes:
Value
4 out of 5
4 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:35 - 44
Gender:Male
Ownership:2 - 7 weeks
Usage:Every day
+34points
Thank you! You have successfully submitted a comment for this review.
Review 5 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Does the Job Well

01/16/2014
By ,
Denison, Texas
5 out of 5
5 out of 5
I purchased the Motorola SURFboard SB6121 DOCSIS 3.0 Cable Modem as an upgrade from a DOCSIS 2 modem so I could take advantage of the higher 50 Mbps speed offered by my cable company. It was very easy to set up: I followed the directions in the startup guide, connected the ethernet cable, and contacted the cable company so they could complete the activation. (If one is setting up cable service for the first time, the steps may be a bit more involved, but the modem itself is not difficult). So far it is working just fine. It looks nice on the desk, doesn't take up a lot of room (it's "footprint" is about 1.5" x 5") and I like that the LED status lights on the front are little icons, so one can tell at a glance which is for power, connectivity, etc.
My previous modem was also a Motorola SURFboard product, and it was working fine after more than 18 months. As earlier mentioned, I only replaced it to be able to upgrade to higher internet speeds. With the cable company wanting $7.99 per month to rent a modem from them, it had already more than paid for itself. I fully expect this one will do the same.
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:55 - 64
Gender:Female
Ownership:1 week or less
Usage:Every day
+23points
Thank you! You have successfully submitted a comment for this review.
Review 6 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Setup was automatic with Comcast cable

10/15/2013
By ,
New Mexico
4 out of 5
4 out of 5
I am not enough of a tech. to know or use all the features but for my 4 lan and 3 wifi house it works perfectly. The modem set itself up and got on line with Comcast automatically. I had to fill in a few questions about my account on line and then it was up and running. I did call Comcast tech support just to make sure all was well and the operator confirmed that the Motorola SB 6121 had setup automatically.
My old Zoom modem worked great for 4 years but then Comcast changed something in their system and it began to drop the connection. Comcast, of course, wanted me to pay $8/month to rent one of their modems. Buying my own from Walmart for less than $80 made more sense to me. The Morotola SB6121 is rated one of the top compatible modems at the Comcast tech site. In another 3-4 years some other change may out date this modem but by then it will have paid for itself 3-4 times over. I guess I need to put the Zoom on craig's list.
Product Attributes:
Value
4 out of 5
4 out of 5
Meets Expectations
4 out of 5
4 out of 5
Recommends this product? Yes
Ownership:2 - 3 months
Usage:Every day
+26points
Thank you! You have successfully submitted a comment for this review.
Read Comment (1)
Read Comments (1)
Customer Avatar
Utah
Wifi?
Posted 07/15/2014
So does this modem have wifi? Is it an all in one modem?
0points
Read Comments (1)
Read Comment (1)
Review 7 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Great modem!

12/23/2012
By ,
Highland, CA
5 out of 5
5 out of 5
I bought this modem after Time Warner decided to start charging a lease fee for their modem. After using it for a full day, I no longer lose my wireless connection on my laptop and have been streaming Netflix all day with no streaming loss. Both of those were huge issues daily. I am more than satisfied with this product!
A word of caution to TWC internet and phone users. The first tech told me if I were to buy my own modem, I would have to return their modem to a TWC store for a phone-only modem. Thankfully, I decided to get the modem up and running before wasting time and gas going to a store with the old modem in tow. The second TWC CS I contacted to add this modem on my account told me I did NOT have to return the old modem; they would just give me the same one (Arris) anyway as it was a phone and internet modem. She hooked me up, removed the modem lease charge and made sure everything was fine with the old modem which is now only working for phone-only. Just make sure to get a 5-1000 splitter (Walmart only had a 5-2000 which works fine) and a 2 more coax cables to hook up both modems.
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:45 - 54
Gender:Female
Ownership:1 week or less
Usage:Every day
+32points
Thank you! You have successfully submitted a comment for this review.
Review 8 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

bought this modem to own myself

05/09/2014
By ,
whiting ,nj
5 out of 5
5 out of 5
if you have cable like Comcast----------MAKE SURE THAT YOU DISCONNECT THE COMCAST MODEM AND TAKE IT BACK TO COMCAST AND TELL THEM YOU OWN YOUR OWN MOODEM NOW00A SAVE-INGS OF 8.00 OFF YOUR BILL AS NO MORE RENT THEIRS-------BECAUSE THIS IS THE ONLY WAY THATA THEIR PHONE OFFICE WILL NE ABLE TO GET YOU UP AND RUNNING--THEY HAVE TO SEE ON THEIR COMPUTERS IN THE BILLING OFFICE THAT YOU RETURNED THEIR OLD MODEM TO YOU BEFORE THEY WILL CONNECT YOU-------SO MAKE SURE YOU FOLLOW THIS ADVICE--IT WILL MAKE YOUR NEW MODEM GET ON LINE RIGHT OFF-----OK THATS THE DEAL THIS MODEM DOES REAL FAST FAST AND I HAVE THE SLOWEST HI SPEED COMCST OFFERS(29.00-PER MONTH) AND IT WILL DO YOUTUBE-VIDEOS LIKE THE FASTEST HISPEED-----SO YOU CAN GET THE CHEAP HI SPEED LIKE I HAVE AND IT WILL WORK FAST WITH THIS MODEM
Recommends this product? Yes
Age:65 or older
Gender:Male
+36points
Thank you! You have successfully submitted a comment for this review.
Review 9 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Delivered the improved speed expected

07/09/2014
By
4 out of 5
4 out of 5
I followed the recommendation from my Internet Service Provider (ISP) to get a DOCSIS 3.0 modem to replace my older model. After carefully looking for reviews, this model was highly rated. It was delivered within the expected time. I was a able to install it right out of the box just following the Read Me First instructions. I noticed the power transformer gets very hot (will keep checking). I performed a speed test and yielded 18.51 Mbps downloading and 7.12 Mbps uploading from an old Sony VAIO (2011) model. My ISP claims it can deliver 25 Mbps. Verifying if the firmware was up to date was rather cumbersome. The firmware loaded 1.0.6.10 is not the latest from the manufacturer, there are other newer versions available 1.0.6.12. I have been using it for 3 days concurrently with 2 MacBooks, one Sony VAIO, and 2 iphone 4s, serviced by a Airave GPS antenna hooked up to the router. Very good!
Product Attributes:
Value
4 out of 5
4 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
+6points
Thank you! You have successfully submitted a comment for this review.
Review 10 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Does exactly what it should. Very stable.

09/15/2014
By
5 out of 5
5 out of 5
What's there to say? Cable modems are very simple; they either work or they don't. This one works just fine, and is the same model I've used in other houses with zero problems. It's the latest specification supported by Cox, and supports bandwidths up to 300-some-odd Mbps, so it's quite future proof for 99% of use case scenarios. Walmart's price and store pickup were great, too. Highly recommended.
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
+5points
Thank you! You have successfully submitted a comment for this review.
Review 11 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Way to save money with the Cable company!

12/14/2014
By
4 out of 5
4 out of 5
Bought this to replace my old, cable company provided modem because I refuse to pay a nickle more to utility companies than I already do especially for an outdated modem! I had an older Motorola SB500 DOCSIS 2 which is so outdated. Checked the cable company website and a rep at the company to make sure this was an approved compatible modem, which for Comcast it is. Upon installing I am getting faster downloads and the best part is saving $8/mo modem lease fees. Should've done this years ago as this purchase pays for itself in a few months. With this modem, you will need a router for WiFi but already had one so it wasn't an issue for me. Very satisfied!
Recommends this product? Yes
0points
Thank you! You have successfully submitted a comment for this review.
Review 12 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Decent Modem (Works with Comcast)

12/07/2014
By
5 out of 5
5 out of 5
My nearly decade old cable modem finally bit the dust and it was time to upgrade. Usually, I would prefer to wait for a sale on device such as this but a lack of functioning internet forced my hand. Price was acceptable, installation was simple and it only took Comcast ~15 minutes to jive with the new modem, once we figured out how to log in to our account that is...
On the day of install speedtest.net by Ookla clocked 27 Mbps down, 11 Mbps up over wifi. More than enough speed for me and easy triple what my old dinosaur modem could deliver.
I would not normally pay full price for the device, but that is not the fault of the retailer who had it in stock when I needed it.
Recommends this product? Yes
0points
Thank you! You have successfully submitted a comment for this review.
Review 13 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

sketchy - Wrong model inside the box -

11/01/2014
By
1 out of 5
1 out of 5
I bought this modem on walmart online store because my old modem was acting weird and walmart is offering a competitive price.
I made the purchase online, picked it up in store, the box was taped up with scotch-tape. something didn't feel right.
3 weeks later, my old modem was acting up again and i thought i can finally use the newly purchased modem, i opened the box and found an brand new, older-model modem sitting inside the box, sealed.
It was a good thing that i didn't open the sealed bags so i was able to make the return, can you imaging if i have opened the plastic bags (remove the seal stickers and etc)
always check your product on the inside and keep the receipt
:Walmart.com
Product Attributes:
Value
1 out of 5
1 out of 5
Meets Expectations
1 out of 5
1 out of 5
Recommends this product? No
+1point
Thank you! You have successfully submitted a comment for this review.
Review 14 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Buy your modem vs. renting

10/15/2014
By ,
Northeast USA
5 out of 5
5 out of 5
I decided to go back to Comcast after having had DSL for 4 years. I weighed the cost of renting at $10.00 per month vs spending $130.00 so this was a no-brainer.
Contrary to what a lot of people have written about Comcast, I never had an issue with them and the tech who came to the house was extremely helpful in setting this up. *NOTE* I did not NEED him to do so, the instructions are easy and simple to follow.
If you have Burst Plus! or any type of package that allows downloads greater than 50 megabyte per second, I would recommend this product.
The two wireless bands of 2.4 and 5.0 ghz provide plenty of options. Just make certain whatever peripheral you use has 5.0 ghz capability before switching because it will not work. And be certain to reset the modem after any changes you make via the online dashboard.
Running wireless, I consistently get 50 megabyte downloads and 12 megabyte uploads. Using an ethernet cable plugged in directly to the modem enables me to get approximately 85 to 90 megabytes but the upload still remains the same at 12 megabytes.
Also of note, I have read a lot of comments about having to tweak Vonage with this modem. I have had no issues whatsoever in connecting Vonage to this modem.
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:35 - 44
Gender:Male
Ownership:2 - 7 weeks
Usage:Every day
+1point
Thank you! You have successfully submitted a comment for this review.
Review 15 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Much better than Comcast provided modem...

12/18/2014
By
5 out of 5
5 out of 5
We were having problems with signal and the old one kept rebooting (~5 min to reboot). This one came and was setup with a simple call to Comcast w/ the model/Ser #. Still had bad signal but this one comes back on line within a minute when disconnected/rebooting. Now the signal is better and this works like a charm.
Recommends this product? Yes
0points
Thank you! You have successfully submitted a comment for this review.
Review 16 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Does the job well!!!

12/17/2014
By
5 out of 5
5 out of 5
I have been using this modem for more then a year and it works fine, never had any issues. Installation is easy and it has all the common features.
Recommends this product? Yes
0points
Thank you! You have successfully submitted a comment for this review.
Review 17 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Works well with Comcast

12/17/2014
By
5 out of 5
5 out of 5
Faster than the Comcast rental box. Works well provides 15mbps according to speedtest website.
Recommends this product? Yes
0points
Thank you! You have successfully submitted a comment for this review.
Review 18 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Lots better than you get from the Cable Company.

10/25/2012
By ,
Auburn, GA
5 out of 5
5 out of 5
Bought it to replace the one from the cable company and right off I saw a greater CLEAR reception, computer loaded faster that I have ever seen it load. And buying it it saves me
$91.00 a year rent, and like I said, it is a better modem! Semper Fi.
Product Attributes:
Value
4 out of 5
4 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:45 - 54
Gender:Female
Ownership:2 - 7 weeks
Usage:Every day
+160points
Thank you! You have successfully submitted a comment for this review.
Review 19 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

works as expected

11/01/2012
By ,
NJ
5 out of 5
5 out of 5
the modem works with comcast (although it took forever to initialize on their network, but that's one time only). it wil pay for itself in a year.
Product Attributes:
Value
4 out of 5
4 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:25 - 34
Gender:Male
Ownership:2 - 7 weeks
Usage:Every day
+37points
Thank you! You have successfully submitted a comment for this review.
Review 20 for ARRIS/Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

Was expecting it to be more difficult

03/29/2013
By ,
South Florida
5 out of 5
5 out of 5
When ordering Comcast internet, I decided to buy a modem rather than pay $7.00 per month for the rental of thier router. I only want internet from Comcast, maybe more later. I was expecting a need to program the unit for it to work properly. I looked for an instruction book for programming and there is'nt one. You must go online for that. I would much prefer a physical manual. It was a surprise to me when I plugged it in and immediately had internet access! Everything worked after a two minute install (plug three cables in). There has not been one glitch! I am happy with the modem and my decision to buy it.
Product Attributes:
Value
4 out of 5
4 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:55 - 64
Gender:Male
Ownership:1 week or less
Usage:Every day
+14points
Thank you! You have successfully submitted a comment for this review.
1-20 of 531 total reviews
1 2 3 4 5  ...  27 Next