Arris Touchstone CM8200A DOCSIS 3.1 Ultra Fast Cable Modem 32X8 Gigabit (Black)

Modem working great on Comcast. I told them it is an SB8200 and they had no problems activating it using the MAC address on the bottom. I'm using Comcast "Blast!" 300Mbps Internet service and an ASUS RT-AC66U router running custom DD-WRT firmware. I'm getting over 300Mbps downloads and a little over 10Mbps uploads on hard wired equipment, which is exactly in line with what I'm paying for. Comcast has additional speed packages in my area (up to 1Gbps) but they are more expensive and I don't need those speeds at this time, however I am confident that this modem could support them if I chose to upgrade.I only went with the CM8200 instead of the SB8200 because I wanted a black device. All my other equipment is black so I wanted something that matches, LOL. The modem does come in non-retail packaging but this just went into the trash, anyway.Note that the 2nd Ethernet port on the modem does not work. From my research this port only works when the device is in LAG (Link Aggregation) mode - if you have a router with two WAN ports, for example. Some people have mentioned being able to get it activated by their ISP's, but this seems very rare.Editing my review to add: approximately two years later, still working great. Now getting over 700Mbps download speeds on a standard Xfinity package. Great modem!

Update 2/13/25- After trying 5 different modems I ended up getting an Xfinity recommended modem which I'm actually getting higher Download speeds and even much higher Upload speeds then advertised. Some non recommended modems can achieve up to the advertised Download speeds but only one fifth the upload speeds. If you are like me, I want to get all the speeds I am paying for, even upload speeds. If you want to get more than advertised speeds you can only achieve that by getting the "Next Gen" recommended modems. Xfinity is revamping their system to give customers more speed but that means they are stopping support and kicking off older modems. See the Xfinity Recommended modems list dated Sept. 2024 that is the most accurate. If you notice this modem is not on the list nor is it supported by Xfinity anymore.I am on Comcast Xfinity and have been for years. Wanted to upgrade to a newer cable modem. I realize this Arris CM8200A is not the white SB8200, but should be the same based on other reviews here and on the Xfinity blogs which has been used with success in the past. I got it since the Amazon description says it is compatible with Comcast Xfinity. I have easily changed my modems many times but the Mac ID on the CM8200A is not recognized by the Comcast system or may now be banned as Comcast is moving onto a newer system and don't want to deal with the support for old legacy modems.

Normally this is limited to cable companies, but this seller on Amazon carries these CM8200a models brand new. They have these on Ebay, but they're all refurbs.Up to 2.5 GBPS speed internet (I only need 1 Gig for now but will upgrade at some point to 2 Gig).Two ethernet ports for 2 separate IPs if you need.It runs Docsis 3.1 format for high spped internet, which should work with almost all internet providers (I have RCN and it works flawlessly).Just remember, you need to call your cable company and tell them you will use your own router. They'll walk you through the process.Instead of renting one for $25/month, this one will pay itself off in less than 8 months' time.Excellent value. This modem won't bottleneck your connection. I have a Netgear router that is awesome, so I tried the Netgear modem and immediately had issues. It's like this Arris modem works better with Netgear than Netgear… weird.Anyway, I'm glad I found this router brand new.Shipped and arrived well before I expected it. Note - the Seller requires signature for delivery.-FLYNT

This cable modem is 5 stars: it works as expected: connected to Comcast in the SF Bay area and I am getting DOCSIS 3.1 enabled 32 channels down and 4 channels up with ping times of 10ms, download speeds of 160 Mbps, and upload speeds of 6 Mbps. YMMV of course. Check them out for yourself on the modem's built in web app at 192.168.100.1 and once activated use www<dot>speedtest<dot>net to determine throughput.A couple of things to note is this is the North America version and once connected, look for the front panel green lights to turn blue which indicates DOCSIS 3.1 connectivity.Ye olde Motorola Surfboard DOCSIS 2.0 had 4x4 channel support. On the Comcast 150 Mbps plan, the CM8200A doesn't make any noticeable difference. Perhaps 4K movies from Netfix and Prime are buffering faster, but it wasn't really a problem before. So keep that in mind if you are upgrading. I upgraded because Comcast said my old modem was no longer supported, I cut the cord recently so I'm watching more videos, and I like to find great deals to run the latest equipment. As another point of reference, I had the 60 Mbps plan with the DOCSIS 2.0 4x4 cable modem for about 3 months and never had a problem watching 4K HDR or Dolby Vision movies. Typically, 4K requires about 25 Mbps download speeds.As many have mentioned, this cable modem will work on Comcast even though it is not listed as a supported device. Tell your Comcast technician it is an Arris Surfboard SB8200 and give them the MAC address listed on the bottom. For me, it didn't work until I rebooted it after waiting the recommended 30 minutes.Next, I am taking off a star because of the seller Chommy85. Not that they are horrible: I did receive the product sooner than expected, it was a great deal at $84 delivered, it is lightly scratch as expected for a used product, and it does work as described above. However, the product was shipped as loose parts in an unpadded bag from USPS. This included the modem, the power supply and an Ethernet cable. These are not delicate parts, but I do expect them to be wrapped securely in box. Now the next Chommy85 issue is more debatable: the price went up $50 dollars since I purchased it 4 days ago. This may be because the modems left in inventory are not scratched, less used, or the market demand is higher. Don't know, but it does make this not as great a deal at about $50 less than a new SB8200. I know I would have purchased the DOCSIS 3.0 SB 6190 new, rather than this modem used, at the new price and saved over $30.Finally, you can find reviews of this modem (OK, the SB8200) and other recent modems here: mbreviews<dot>com/category/modems Frankly, unless you are running a business this DOCSIS 3.1 modem is likely over spec'd for what you can actually use in a home network. But if you find a great deal on it, be assured the CM8200A won't be the problem behind any bandwidth issues on your network for years to come.