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NETGEAR CM3000-100NAR Nighthawk CM3000 DOCSIS 3.1 Mid/high-Split Cable Modem, Up to 2.5Gbps, Black - Certified Refurbished
Amazon Renewed

NETGEAR CM3000-100NAR Nighthawk CM3000 DOCSIS 3.1 Mid/high-Split Cable Modem

Bottom line: The NETGEAR CM3000-100NAR Nighthawk CM3000 DOCSIS 3.1 Mid/high-Split: DOCSIS 3.1 mid/high-split supports Xfinity 2 Gbps down / 200 Mbps up tiers; main trade-off: certified Refurbished, not new - cosmetic wear and shorter coverage are possible.

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By , Founder & Editor-in-Chief · Listing data updated

Mike Perry — Hardware researcher since 2014, focused on GPU performance across gaming, rendering, and local-LLM inference. Synthesises community benchmarks, manufacturer specs, and public forum data into actionable buying guides.

Pros & Cons

Pros

  • ✓ DOCSIS 3.1 mid/high-split supports Xfinity 2 Gbps down / 200 Mbps up tiers
  • ✓ 2.5Gbps auto-sensing LAN port avoids the 1Gbps bottleneck on multi-gig plans
  • ✓ Two extra 1Gbps ports support link aggregation for a second router or switch
  • ✓ 32x8 SC-QAM plus 2 OFDM down / 2 OFDMA up channel bonding

Cons

  • ✗ Certified Refurbished, not new - cosmetic wear and shorter coverage are possible
  • ✗ Modem only: no Wi-Fi, so you still need your own router
  • ✗ Mid/high-split speeds require an ISP plan that actually provisions them
  • ✗ Sold under the Amazon Renewed brand, so warranty terms vary by seller

Manufacturer description

Upgrade to faster speeds with the revolutionary DOCSIS 3.1 mid/high-split cable modem from NETGEAR. The Nighthawk CM3000 DOCSIS 3.1 High Speed Cable Modem is specifically engineered to handle today’s fastest DOCSIS 3.1 cable Internet speeds that can only be accessed with mid/high-split technology, such as Xfinity’s 2 Gbps Internet download speeds and 200 Mbps upload speeds. Your entire family can enjoy unprecedented download speeds up to 2.5 Gbps and faster upload speeds up to 1 Gbps for lag-free gaming, crisp video conferencing, smoother music and video streaming, and instant app downloads…

SpecPicks Verdict

SpecPicks scored NETGEAR CM3000-100NAR Nighthawk CM3000 DOCSIS 3.1 Mid/high-Split… using a rating × review-volume × price-fit model applied to published specs and reviews across the PC & gaming hardware category. Amazon Renewed's PC & gaming hardware lineup sits within the broader category mid-tier; price and specs are the deciding factors over brand loyalty here. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.

Common buyer scenarios for PC & gaming hardware of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the retailer's listing before purchase. Prices and stock are set by the retailer and may have moved since this page was last updated.

Key Features

  • 32 downstream and 8 upstream SC-QAM channels. 2 OFDM Downstream channels and 2 OFDMA Upstream channels.
  • One LAN 2.5Gbps Gigabit Ethernet port with auto-sensing technology. Two LAN 1Gbps Gigabit Ethernet ports with support for link aggregation.
  • One WAN coaxial cable connection. IPv6 next-generation Internet addressing support.

Full Specifications

BrandNETGEAR
ColorBlack
Unit Count1 Count
Model NumberCM3000-100NA
Built-In MediaNighthawk High-Split 2.5Gbps Internet Speed Cable Modem (CM3000), One (1) Ethernet cable, Power adapter, Quick install guide
Mfr Part NumberCM3000-100NAS-cr
Number of Ports2
Compatible DevicesRouter, Personal Computer, Laptop
Data Transfer Rate2500 megabits_per_second
Warranty Description90 days limited warranty
Connectivity TechnologyEthernet
Number of Ethernet Ports3
Internet Service ProviderXfinity, Cable providers
Internet service providerXfinity, Cable providers
Maximum Upstream Data Transfer Rate100 megabits_per_second
Maximum Downstream Data Transfer Rate1 gigabits_per_second
Full listing titleNETGEAR CM3000-100NAR Nighthawk CM3000 DOCSIS 3.1 Mid/high-Split Cable Modem, Up to 2.5Gbps, Black - Certified Refurbished

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NETGEAR CM3000-100NAR Nighthawk CM3000 DOCSIS 3.1 Mid/high-Split Cable Modem, Up to 2.5Gbps, Black - Certified Refurbished is listed on Amazon. Price, availability, shipping and returns are set by Amazon and its sellers — check the listing for current terms. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.

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NETGEAR CM3000-100NAR Nighthawk CM3000 DOCSIS 3.1 Mid/high-Split Cable Modem, Up to 2.5Gbps, Black - Certified Refurbished
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