Features:

  • Approved on Comcast Xfinity, Spectrum (Charter, Time Warner, Brighthouse Networks), Cox, Mediacom, Suddenlink and most other US Cable Internet Providers. NOT compatible with Verizon, AT&T or Centurylink. REQUIRES Internet Service.
  • Wired modem only. Does not include WiFi router or VOIP Telephone adapter. Gigabit Etherent port to connect to PC or Router.
  • 8 Download Channels and 4 Upload Channels capable of up to 343 Mbps download and 131 upload speeds. Recommended for Internet Plans up to 100 Mbps.
  • Brown Box Models Not Valid for this Item when Sold As New, should Report to Amazon Immediately and Return to Seller
  • 2 year warranty with US based customer service. Refer to the Quick Start Guide and Installation video. Supports IPv4 and IPv6 – the latest Internet standard
So far so good. I got fed up with Comcast's dumpy modem/router ...

So far so good. I got fed up with Comcast's dumpy modem/router that kept going offline, so I decided to drop their equipment (saving me $10.00 a month) and just buy my own. This modem/router works great and was easy to setup with Comcast (just plug in an ethernet cable from your computer to the modem while it's connected to your coax, and the Comcast activation page should automatically come up when you open your browser). Speeds of 240mbps both wired and wireless (I pay for 200mbps). Great wireless coverage in the house (I live in a 3 story town house and full bars anywhere in the house). One thing to note, your wireless might be slow-er on the 5Ghz channel than it should be because the router defaults to a 20Mhz band. You can change it to an 80Mhz band in the router's configuration settings. I was getting only 70mbps on the 20Mhz; once I switched it to the 80Mhz band it jumped to 240mbps!

Smoking Hot

I had a Motorola SB6580 that this replaced. I wanted to try this because of the additional channel bonding and capability for IPv6. I was Getting 54Mbs with the 6580 and then this baby rocks in at 72Mbs ! I was stoked. One note I was not prepared for-this thing is the size of a small form factor computer! it is HUGE. Make sure you take size into account. I am very impressed.,, others have complained about the brightness of the lights on the front panel. Not an issue in my opinion.

Solid Connection and Reliable

My ISP is Comcast and this works excellent with there service. I don't ever experience lag when gaming and streaming at the same time. However, the speed and lag really depends on what you are paying for. This pretty much pays for itself since I don't have to worry about paying a monthly equipment rental fee. It's been extremely reliable and hasn't failed me yet. I've been using it for about 8 months now and always have a solid connection. Setup is easy. It's literally plug and play. It does get warm but it is running 24/7. The status and notification lights are bright when it's dark so keep that in mind when deciding where to put the router. I like the fact that the wireless capability is also built in. Not all router comes with wireless capability requiring you to supplement this by purchasing an additional router that can produce a wireless signal. Another feature I like is that the router is dual band. Able to provide a 2.4Ghz and 5Ghz band. This is more important if you live in an apartment but a nice to have. I live in a two story house that is approximately over 2000+ square foot. I'm able to have an internet connection anywhere I go in this area inside and outside. Switch your device to the 2.4Ghz band the further you go away from the router to have the best signal and speed.

Very Strong Wifi - Consistent Speeds (Cox Cable)

We were hanging on to our old modem and router setup for as long as we could, until we started to have repeated issues with frequent disconnects. We purchased a TP Link modem router, and had two duds, so I took my time to do some research, and came across this. It has 2 gigabit ethernet ports, however with most devices using wifi to connect, this wasn't a problem as I only needed to hardwire the computer. Speedtests are very consistent, and even at peak times, we are hitting 95 Mbps on a 100 Mbps plan with Cox Cable. Although we don't have anywhere near 300+ Mbps, we picked this up in the event we decided to upgrade to a new tier of internet. The wifi has great range, we live in a 2 1/2 story house, and have excellent coverage throughout the house. The unit sits on the main level on the north end of the house, and our FireTV stick and Xbox are on the opposite end of the house in the basement, and have yet to have any disconnects that used to plague us with our old set up. Setup was easy. I had it plugged in, all cables connected and called Cox. They asked for model number and Mac Address (All located on the bottom of the unit or inside box), they reset the device remotely, and once it cycled on, we were connected and finished. Having just one device to deal with made the process quick and easy. Also to note, it was a much smaller unit than I expected, and doesn't take up too much space. I definitely recommend this to anyone who wants to upgrade to a Modem Router, it is worth it, I made the mistake of going with a cheaper TP Link, and it crashed and burned...twice. Spending a little bit more in this case makes the difference.

ABCDE[ ]GHIJK Comcast

Comcast. The name alone stirs some anger inside countless people burned by their price gouging. Leasing their equipment is one of the ways they stick it to you ($10/month... no, thank you). This unit (SB6121) is among a few of the 3-star certified models (highest certification), according to Comcast's own research (mydeviceinfo.xfinity.com). That information gave me more confidence in my choice, so I thought I'd share here. For the price point, and the "speed" I subscribe to, this unit is a perfect fit and will pay itself off in only a few months. Setting it up was relatively easy online. Just hook it up directly to a computer via Ethernet and go to xfinity.com/activate (for Comcast users, obviously). It took a couple minutes and I had to disable WiFi on my laptop, but all in all a pretty easy process. So far, not a single issue with streaming Netflix, Hulu, Amazon Prime or general web surfing. Will update my review should any issues arise, but for now, no news is good news. Quick shout out to the seller, Stevens2000. Unit arrived three days earlier than Amazon's earliest estimated arrival date. I wasn't in a major rush, but that was a delightful surprise.

Easy install, fast speeds, and no issues so far!

Swapped out my Comcast rental modem, was up and running in just a few minutes, and now I don't have to pay the $7 modem rental fee to Comcast. I'm provisioned for the 105/20 Mbps package and typically get 120/20.5 Mbps. This modem can utilize up to 8 channels of downstream for a theoretical max speed of 343 Mbps whereas the Motorola SB6121 and other earlier/cheaper DOCSIS 3 modems can only utilize 4 channels maxing your download speeds out at 172 Mbps. Just something to think about if you plan on using this modem for a few years as speeds offered will inevitably increase. Also, it *does* support IPv6 even though Comcast's page doesn't list it as certified yet. Motorola's data sheet specifically lists the SB6141 as IPv6 ready and tests with an Apple AirPort Extreme (v7.6.4) and MacBook Pro running 10.9 confirm this. Update 2/4/13: Still working great without issue. Update 3/25/13: Still not even a single reboot required. Update 8/28/13: Still working great... Update 7/8/14: First issue... had an outage for 15 min. Reset the modem and it didn't resolve the issue. Called Comcast, they reset something on their end and I was up and running again. First issue since I bought it. Update 4/5/2015: Comcast recently upgraded my speed tier and I'm consistently getting speeds up to 180/25 Mbps.

Be sure this modem is accepted by your ISP

CAUTION: Before you order this modem, be sure to verify that the modem is one that is accepted by your Internet Provider! Our online experience goes back to the dial-up days of Prodigy and AOL. We were thrilled just to get improvements in that dial-up speed. For all of these years we accepted and used whatever modem/router the ISP provided. We slowly began to realize that we might be able to buy and use our own equipment, but we weren't really sure what to do. Our son pointed us to this modem, so a few days ago we ordered it from amazon. We are thrilled and satisfied. The setup was very easy, even for an old man with mid-range tech abilities. Attach the incoming COAX cable from the wall, connect a CAT 5 cable from the modem to the router, and you're done, except for one big thing, getting your ISP to activate the new modem. In our case that turned out to be a long process. Apparently some mistakes were made on their end, but the job did get done eventually. Some of the complications were the result of our wanting to keep our VOIP phone connection, and that required that we keep our ISP's modem/router for just that one service. If you don't have that requirement, then you should have a much easier job. Regarding results? Absolutely great! We may need to add one caution. We weren't quite sure about what steps in the installation to follow, in what order. Follow the printed instructions to make the connections. When that is done, call your ISP, tell the real/recorded voice that you want to activate a modem, and they will take care of the job.

I'm a big fan of this modem.

Your cable internet modem is the small table top appliance that allows you to get on the internet via a signal from your cable company. Your modem's unique MAC ID (found on the box and modem itself) must be registered with, and activated by, the cable company for the modem to work properly. Time Warner Cable, Comcast Cable, and Cox Cable charge $7 to $10 per month (and climbing) to lease or rent your cable internet modem from them. (In this review, I use the terms "lease" and "rent" interchangeably). Quick math says you're paying $84 to $120 per year to use their modems. All three companies allow you to buy your own modem and stop paying the monthly fee. You can easily buy a quality modem for under $85. In any event, the payback is LESS than 1 year. Even if you did need to replace your modem every two years with what might be the latest and greatest, you would still come out way ahead. My original modem hadn't been updated or replaced by my cable company in at least three years and they still wanted me to pay to rent it. Buying and installing your own modem is a very easy process. The easiest way to determine which modem you need is to check your model number (located on the front, back or bottom of your modem) and simply buy the same modem as your current model --- as you KNOW it'll work --- although you'd very likely get better performance with a newer model. If your current model isn't one of the ones listed in the cable provided site lists, then you have an old modem that needs replacing anyway. This is a DOCSIS 3.0 model. A DOCSIS 3.0 cable modem is backwards compatible, so you can buy one of these even if you currently have a DOCSIS 2.0 modem. Suffice it to say the dual band feature of the DOCSIS 3.0 modem is up to 8x faster. Buy the white SB6141 if you already have a router. Buy the black SBG6580 if you don't. HINTS: 1.There are lots of modems that look similar to the approved modems. Be sure to get the EXACT model number shown in the "approved lists" located on your internet provider's website. This modem is approved by all three. 2.Although you can make due with lower end models if you have basic internet service, I strongly recommend you consider buying a DOCSIS 3 model that is also IPv6-ready. 3.DOCSIS 3 modems (also known as "Dual Band") are simply faster modems than DOCSIS 2 (also known as "Single Band") due to their ability to double the download speed bandwidth. Most folks will see an improvement with a DOCSIS 3 modem. Keep in mind that the cable companies often increase the internet speed of their entire system from time to time. The speeds you have today are higher than the speeds they provided a decade ago on the same service plan. DOCSIS 2 modems are cheaper for a reason. Don't fall into that trap, unless you never want higher internet speeds. 4. The Internet is transitioning from shorter Internet Protocol (IP) addresses (aka IPv4) to longer Internet Protocol (IP) addresses (aka IPv6) due to a shortage of short addresses. To make sure that the Internet can keep growing, a new numbering system called IP version 6 (IPv6) is being deployed and at some point IPv4 modems will not be able to connect to the new addresses. IPv6-ready modems will allow you to access all of the internet addresses now and after the IPv4's are no longer supported. 5.Yes, you can also replace your Gateway modem (a modem with a built-in Wi-Fi router) and discontinue your rent payments. This modem is white. The LED lights on this modem are so bright they can be used as a night light. If this is a problem for you, simple apply a piece of opaque tape to the front panel. If you already have a router, this is the one to choose between these two. (Caution: A black-colored SB6141 is also available. Don't buy it! Even though it's usually a couple dollars cheaper, it's an older OEM model which has no warranty, may not have the most current firmware, and may have been remanufactured).

Speedy And Simple

Got this to replace my aging, Comcast provided Arris modem of 3 years to boost performance and save $10 a month on modem rent. There's a 2 page user guide that comes with the router which explains everything you need to know (simplicity). I plugged the thing in, opened a browser and was immediately prompted to activate the new router via an automated Comcast setup wizard and presto! Online. The only minor tweaks needed are setting up a strong password for the admin account, enabling "auto" channel selection for the 5GHz range, and enabling "band steering" (read the help tooltip in the router admin page: wireless > performance enhancements). Once set up, it appears my average bandwidth has about doubled and my ping even dropped a few milliseconds on average! Not bad. This purchase seems to have allowed me to get the full speed I pay for. Funny that Comcast never mentioned this. Or not funny. But typical. DIY, buy this and send the old piece of junk back to Comcast and save $10. You won't regret it. PS: The two blue send/receive LEDs on the front are crazy bright and kind of annoying at night. Disable them in Basic > LED Control

Fast

I purchased this SB6141 to replace my VERY old Linksys DOCSIS 1.0 modem. I recently upgraded to 75mb download from RCN (Chicago) and DOCSIS 1.0 was going to bottleneck my speed. The modem (as are all modems) was extremely easy to install. Plug in, call ISP and you are good. The speeds are fantastically fast and this modem was well worth the price. ****I purchased this white SB6141 over the black SB6141 for one main reason. If you do your research you will notice that the Black SB6141 are only issued to ISP's from Motorola. Meaning, if you purchase a black model from Amazon (or any store), you are purchasing a used or refurbished product (they also ship in ordinary brown cardboard boxes). The only consumer model of the SB6141 is the white model which ships in traditional packaging. The white model is THE ONLY model that comes with a warranty from Motorola. I know this because I called Motorola twice and spoke to two (2) different reps who said the same thing; "Black boxes are for ISP's and do not have a warranty while the white boxes are for consumers and come with a warranty". Further complicating matters is that the black SB6141's usually have old firmware on them because they were generally made a few years ago. White SB6141 have newer or the newest firmware because they are shipping directly from the manufacturer. Your ISP may or may not flash customer owned modems to the newest firmware. If you purchase the Black model, you might be purchasing a 3 year old modem with no chance of upgrading it (also remember that you cannot flash your own modem's firmware). Do yourself a favor and research this white consumer model over the black ISP model before you pull the trigger. I spent 20 bucks more for the white SB6141 so I could have peace of mind and I would strongly encourage you to do the same.***** The only "con" I have about this modem is that the blue lights on the modem ARE BRIGHT AS @#%&$. Seriously, at night, my living room is glowing blue from the lights. I really cannot express enough how bright the lights are. You were warned.

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