NETGEAR Nighthawk CM3000 DOCSIS 3.1 cable modem: specs and compatibility

The NETGEAR Nighthawk CM3000 is a cable modem that you own and plug into your cable internet line, instead of using one supplied by your provider. It supports DOCSIS 3.1 with mid/high-split, which is what the fastest cable plans require. NETGEAR says it handles plans up to 2.5 Gbps and is made for use in the US only.

What mid/high-split means

Cable networks divide their frequencies between downstream (to you) and upstream (from you). Older networks reserved only a narrow slice for upstream, which capped upload speeds. Mid-split and high-split designs widen the upstream slice, and a modem must support the new split to use it. NETGEAR says the CM3000 does, and it describes uploads as up to ten times faster than older standards. That helps with video calls, large uploads, cloud backups and remote access to cameras or storage.

Speeds

NETGEAR rates the modem at up to 2.5 Gbps down and 1 Gbps up. It cites plans such as 2 Gbps down and 200 Mbps up as examples of what it is built for. These are the modem's limits. Your actual speed depends on your plan, your provider's network, your router and the device you are using.

Ports and connecting to a router

There is one 2.5 Gigabit Ethernet port and two Gigabit ports:

• 2.5 Gig port: connect it to a router's multi-gig internet port to get above 1 Gbps on a single cable.
• Two Gigabit ports: with a router that supports link aggregation, they can be combined for up to 2 Gbps.

For the most from the modem, NETGEAR suggests a Wi-Fi 6E or Wi-Fi 7 router or an Orbi mesh system. A modem faster than your router wastes the difference, so check the router's internet port speed.

Owning your modem

NETGEAR says that buying a modem can save on provider rental fees, which is a main reason people buy one. The details depend on your provider's terms, so check them.

Compatibility

The listing says it works with all major US cable providers, including Xfinity, Spectrum and Cox. Providers keep their own lists of approved modems, and they must activate the modem on their network. Check the current list before buying, as the approved models change. It is designed for the US only.

Size

It measures about 6.8 x 3.7 x 8.2 inches (17 x 9.4 x 21 cm) and weighs 1.1 lb (about 500 g).

Who it suits

It suits households and small offices on a cable plan, especially a fast one, who want upload speed and a multi-gig connection to a router, and who are happy to set up their own equipment.

What to check before you buy

• Your provider and plan: confirm that the modem is approved and supports your plan's speeds.
• Your router: look for a 2.5 Gbps internet port, or use link aggregation.
• Not a router: it does not provide Wi-Fi, so you need a separate router.
• Activation: you may have to call or use an app to activate it.
• Cabling: use quality coax and Ethernet cables rated for the speeds you are using.
• Region: it is made for the US only.

The short version

• A DOCSIS 3.1 mid/high-split cable modem rated up to 2.5 Gbps down and 1 Gbps up.
• One 2.5 Gig and two Gigabit Ethernet ports.
• Meant for a separate Wi-Fi 6E or Wi-Fi 7 router, or an Orbi system.
• Works with major US cable providers once activated; US only.

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