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Motorola SBG6782-AC Surfboard eXtreme Cable Modem review: A complete, but bulky, cable Internet gateway


For owners of an out-of-date cable Internet gateway or for new cable Internet customers, the new Motorola SBG6782-AC Surfboard eXtreme Cable Modem would make a great investment.

The SURFboard eXtreme is so much larger than a standalone cable modem.

Motorola SBG6782-AC Surfboard eXtreme Cable Modem

The Good

The <b>Motorola SBG6782-AC Surfboard eXtreme</b> offers high-end hardware components and good overall performance. The built-in support for MoCA is a useful extra.

The Bad

The device is perhaps bulky enough to defeat the purpose of having a combo device, its Wi-Fi speed could use some improvement over long range, and the ridiculously lengthy name can be a headache during the modem setup process.

The Bottom Line

If you're looking to upgrade your existing cable-Internet-based home network, or start anew, the Motorola SBG6782-AC is currently the most complete and advanced all-in-one modem-router combo you can get. Non-cable users need not apply.

This is the first modem-router combo device that's comparable to, and even better in some cases than, using a standalone modem and a separate Wi-Fi router. The new device uses high-end hardware components, and even has built-in support for MoCA (an Ethernet-Over-Coax standard), which is a great bonus for those looking to expand a wired home network using the existing coaxial cables that bring a TV signal to different rooms.

In my testing, the Motorola SBG6782-AC offered mixed, though overall very good, performance as both a DOCSIS 3.0 cable modem and a high-end router. As a true dual-band device, it also supports all existing Wi-Fi clients on the market. On the downside, it's unusually bulky, it has no USB port, and it provides subpar Wi-Fi speeds at long range on the 2.4GHz frequency band. Its lengthy name, believe it or not, can also cause trouble during the modem setup process.

All in all, at $200 the Motorola SBG6782-AC definitely beats getting a standalone cable modem and a separate Wi-Fi router with similar high-end specs, in terms of startup cost. However, if you already have a robust home network with a fast cable modem, there's no need to upgrade.

Device type Cable modem/ Wi-Fi router combo
Dimensions (HWL) 8.8x2.1x10.1 inches
Router specs True dual-band 802.11ac/n/g/b with four Gigabit LAN ports
Modem specs DOCSIS 3.0 / Up to 343Mbps WAN speed
Wi-Fi security WEP, WPA,WPA2 with Wi-Fi Protected Setup
IPv6 support Yes
Extra features Built-in MoCA 1.1 support
Current cost / warranty $200 / one-year limited

Bulky but most complete all-in-one design
Standing 8.8 inches tall, 2.1 inches wide, and 10.1 inches deep, the Motorola SBG6782-AC is very bulky, significantly larger than even a Wi-Fi router and a standalone cable modem put together. But it's large for a good reason: it has the most functions bundled in a single box that I've seen yet, consisting of a high-end 802.11ac-enabled true dual-band Gigabit router, a DOCSIS 3.0 cable modem, and a MoCA 1.1 adapter.

The Surfboard eXtreme is much larger than a standalone cable modem.
The new Surfboard eXtreme combo device is much larger than a standalone cable modem. Dong Ngo/CNET

On the back the Motorola SBG6782-AC has four Gigabit LAN ports for connecting wired clients and one coaxial F connector to connect to a cable TV line-in. There's no other WAN port, meaning you can't use this device as a standard router for other Internet services, such as DSL or satellite disk. The device doesn't have a USB port, either, so there's no support for a USB printer or storage.

However, it does what it needs to. With a standalone cable modem, you would need a separate router to provide Internet access to multiple devices, but with the Motorola SBG6782-AC, all you have to do is connect the coaxial connector to the cable TV line-in and your home network is pretty much ready. There are no other hardware devices needed.

Since the coaxial connector also supports MoCA, which is similar to a power line connection but uses coaxial TV cables instead of electrical wiring, you just need to get MoCA adapters at the far ends to add more wired devices to the home network. This is a great way to expand a network for homes that are wired with TV cables.

On top the device has a Wi-Fi Protected Setup (WPS) button that helps quickly add WPS-enabled devices to its Wi-Fi networks. And on the front, there are the usual status lights that you can glance at to see how well the device is working.

What's in a name?
Setting up the Surfboard eXtreme could be a lot easier if the device had a simpler and single name. Instead it has many small variations.

The lengthy name on the box here is just one of many equally confusing names the device is identified with.
The lengthy name on the box here is just one of many equally confusing ones the device is identified with. Dong Ngo/CNET

On the box, its name is: Motorola Surfboard eXtreme Cable Modem & Wi-Fi AC Router with MoCA. At the company's Web site, the device's name is Motorola SBG6782-AC Surfboard eXtreme Cable Modem. The device is marketed at retailers as Motorola - Surfboard eXtreme 802.11ac DOCSIS 3.0 Cable Modem and 4-Port Gigabit Ethernet Router. Finally, on a cable Internet provider's supported list, it's identified as simply SBG6782AC or SBG6782AC DOCSIS 3.0 Wireless Cable Modem Gateway.

And that's not all, since the Arris Group acquired Motorola's Home unit back in April, you will also see its above names available with the "by ARRIS" suffix. And in the end, you're not sure if this device is from Arris or Motorola.

While this seems like no big deal, it could be a big headache when you call your cable provider to register the device's modem, a required step to make the Internet work. In my case, the Comcast technician on the phone at first insisted that he couldn't activate the device since it "wasn't on the approved list" when I told him the device's name. To make the story short, make sure you check with your provider's approved list of cable modems (here's Comcast's list, for example) to find out how this device is named at their end. Most of the time, using the model number Motorola SBG6782AC is the safest way.

Robust Web interface, great feature set
Other than any trouble arising from its name, the Surfboard eXtreme is very easily to set up thanks to its robust Web interface. The router part of it is set up the same way as a typical home router. (Read more about how to set up a home router here).

The Surfboard eXtreme has a robust and self-explanatory Web interface with lots of features, including the ability to show level of interference for its Wi-Fi networks.
The Surfboard eXtreme has a robust and self-explanatory Web interface with lots of features, including showing level of interference for its Wi-Fi networks. Dong Ngo/CNET

Basically, from any connected computer you can access the device's interface by pointing a Web browser to its default IP address, which is, and log in with the admin account with the default username and password, which are "admin" and "motorola."

After that, you'll be greeted with a self-explanatory interface, where you can manually change the device's settings or follow onscreen wizards.

The SBG6782-AC has a lot more settings and features than other Motorola combo devices I've had experience with. It's a true dual-band Wi-Fi router with support for the top-tier 1.3Gbps 802.11ac standard on the 5GHz band. For regular 802.11n clients, it offers up to 450Mbps on both the 5GHz and the 2.4GHz bands, which is also the top tier of this standard. You can set up two main Wi-Fi networks (one for each band) and two Guest networks as well. Wi-Fi clients connected to the Guest networks can access the Internet but not local resources, such as a printer or shared files.

Uniquely with the device, when setting up the Wi-Fi network, the interface automatically shows the interference level of the Wi-Fi channel you've selected. This way you can manually pick the channel that's most likely to have the best signal quality. Or you can also pick the Auto option to let the device take care of that for you. This is very helpful, especially on the 2.4GHz band since your neighborhood very likely is saturated with routers and access points using the same frequency band.

Other than that, the Motorola has common features collectively found in high-end routers, such as FireWire, Web filtering, Parental Control, and QoS. There is also support for dynamic DNS service, port-forwarding, reserved IP address, and so on, for those wanting to run multiple servers and remote applications on the network.

All in all, the router part of the Surfboard offers most of what advanced users would expect in a high-end router.

The Motorola SBG6782-AC's coax cable connector also works as a MoCA 1.1 adapter.
The Motorola SBG6782-AC's coax cable connector also works as a MoCA 1.1 adapter. Dong Ngo/CNET

The Motorola SBG6782-AC did very well in my tests as a cable modem, offering the same Internet speed as my existing DOCSIS 3.0 modem. Since Internet speed depends on how much you pay, I didn't get to test the device up to its top claimed speed of 343Mbps. However, I believe most cable Internet users won't see their Internet speed reduced because of this device. I know for sure this new device works with Comcast, but if you use other cable providers, make sure to check with them to see if the SBG6782-AC is supported before getting it.

As a Wi-Fi router, the SBG6782-AC offered mixed performance in my testing, though overall it did well.

CNET Labs 802.11ac performance (in Mbps)
(Longer bars indicate better performance)

Asus RT-AC66U

Netgear R6300

Motorola Surfboard eXtreme SBG6782-AC

D-Link DIR-865L

When used with 801.11ac clients, which only work on the 5GHz band, it offered a sustained speed of 293Mbps at close range (15 feet), putting it in the top three on the chart. When I increased the range to 100 feet, the speed was reduced to 146Mbps, slightly below the average. Nonetheless, these are very fast Wi-Fi speeds.

When used with 802.11n clients on the 5GHz band, the Motorola scored 186Mbps and 122Mbps for close range and long range, respectively. Both of these were around the average on the charts. On the 2.4GHz band, it registered 63Mbps and 19Mbps for close range and long range respectively, not so impressive.

CNET Labs 2.4GHz Wireless-N performance (in Mbps)
(Longer bars indicate better performance)

D-Link DIR-868L

Motorola Surfboard eXtreme SBG6782-AC

Asus RT-N66U

Netgear R6300

D-Link DIR-857

Netgear WNDR4500

Asus RT-AC66U

CNET Labs 5GHz Wireless-N performance (in Mbps)
(Longer bars indicate better performance)

D-Link DIR-857

Asus RT-AC66U

Linksys EA4500

Motorola Surfboard eXtreme SBG6782-AC

Asus RT-N66U

Netgear R6300

D-Link DIR-868L

D-Link DIR-865L

The Motorola SBG6782-AC offered very good range in my testing, up to some 280 feet away. Its effective range, however, is around 150 feet. I also tested the device's Wi-Fi signal stability and it passed with flying colors, with three days of continuous connection.

A bit of a disclaimer: I tested the Motorola SBG6782-AC's router at CNET's offices where there are walls and many other Wi-Fi devices that were out of my control. As with all Wi-Fi routers, your results may vary depending on where you live.

I wasn't able to test the Motorola SBG6782-AC's MoCA feature since our test labs, as well as my home, weren't wired for that. But like power line connectivity, this feature should work quite straightforwardly.

The Motorola SBG6782-AC Surfboard eXtreme is an exciting product since it's the first among combo devices to come with top hardware and lots of features. The device's performance is also great for the most part. It would earn higher ratings, however, if it were a bit slimmer or offered better Wi-Fi speed over long range. In its current state, all things considered, it's still the best combo device for cable Internet users.

The SURFboard eXtreme is so much larger than a standalone cable modem.

Motorola SBG6782-AC Surfboard eXtreme Cable Modem

Score Breakdown

Setup 6Features 9Performance 7Support 8