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Motorola SURFboard SB6121 — Review & Specs | Pricepect | Pricepect

Home ModemsMotorola SURFboard SB6121

Motorola SURFboard SB6121 — image 1

Arris

Motorola SURFboard SB6121

$105.46

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SB6121BlackMax Download Speed: 172 Mbps 1 year

Expert Review Analysis

The Arris Motorola SURFboard SB6121 is a DOCSIS 3.0 cable modem with 4‑downstream and 4‑upstream channel bonding, delivering up to 171.5 Mbps download and 131 Mbps upload. It features a Gigabit Ethernet port, ENERGY STAR certification, and broad compatibility with major cable providers, making it a solid choice for budget‑conscious households with mid‑tier plans.

✓ Best for: Budget‑conscious households with cable internet plans up to ~172 Mbps who prefer a wired Ethernet connection, need ENERGY STAR efficiency, and are using major providers like Comcast, Cox, or Charter.✗ Not ideal for: Subscribers on gigabit or high‑speed (>300 Mbps) plans, users who rely on built‑in Wi‑Fi, or anyone seeking a future‑proof modem that supports the latest DOCSIS 3.1 standards.

Pros

✓Supports 4x4 channel bonding delivering up to 171.5 Mbps download and 131 Mbps upload for HD streaming and gaming.
✓Includes a Gigabit Ethernet (10/100/1000Base‑T) RJ‑45 port with Auto‑MDIX for high‑speed wired connections.
✓

Price History

Current

$105.46

Average

$77.15

Lowest

$34.03

Highest

$106.00

Price trend (90d):+0.4%

Best Seller Rank History

Now#109Best#89Worst#198 +26

Lower = better sales rank

Rating Trend

Rating4.3/ 5Reviews11,660+-89 reviews -0.10

Specifications

Accessories

Included AccessoriesModem, Ethernet cable, power cable, installation sheet

Design

Height8.7 Inches mm

Width6.4 Inches mm

Depth2.0 Inches mm

Weight1.0 Pounds g

ColorBlack

Features

Front Panel LEDsPower, Ethernet, Online, etc.

General

BrandArris

ManufacturerMotorola

Model NameSB6121

Release Date2013-06-01

Warranty1 year

Network

Downstream Channels4 bonded

Upstream Channels4 bonded

Performance

Max Download Speed172 Mbps Mbps

Max Upload Speed131.072 Mbps Mbps

Downstream Max Theoretical Data Rate171.537 Mbps (4 channels) Mbps

Upstream Max Theoretical Data Rate131.072 Mbps (4 channels) Mbps

Downstream Modulation64/256 QAM

Ports

Ethernet Ports1 Gigabit (RJ-45)

Power

ENERGY STAR CertifiedYes

Certification

ENERGY STARCertified for low power consumption

Power Feature

Energy Conservation SwitchOptional switch to reduce power usage when idle

Indicators

Front‑panel LEDsDisplays power, Ethernet link, online status, and bonded channel activity

Network Protocols

IPv4/IPv6 SupportCompatible with both IPv4 and IPv6 addressing

Security

AES EncryptionSupports AES encryption for secure data transmission

Dimensions & Weight

Height8.7 Inches

Width6.4 Inches

Depth2.0 Inches

Weight1.0 Pounds

Research Sources

gditechnology.com

ahtechsolutions.com

officedepot.com

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User Reviews

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4.3

(11,660 reviews)

ENERGY STAR certified with optional Energy Conservation Switch to reduce power consumption when idle.

✓Broad compatibility with major cable providers (Comcast, Cox, Charter) and IPv4/IPv6 plus AES encryption.

✓Front‑panel LED indicators provide clear status for power, Ethernet link, and bonded channel activity.

Cons

✗DOCSIS 3.0 technology is outdated and cannot fully utilize modern gigabit‑speed cable plans.
✗Many ISPs (e.g., Cox) cap the modem’s effective throughput at around 50 Mbps, limiting its usefulness on faster plans.
✗Lacks built‑in Wi‑Fi and offers only a single Ethernet port, requiring an external router for wireless devices.
✗Refurbished units are commonly sold, which may lead to inconsistent performance or reduced lifespan.
✗Maximum downstream capacity (4 channels) is lower than newer models, resulting in lower real‑world speeds on high‑tier plans.

From Expert Reviews

Praised by Experts

✓Manufacturer highlights the 4×4 DOCSIS 3.0 channel bonding as a “lightning‑fast broadband” solution.
✓Energy‑efficiency emphasized through ENERGY STAR certification and an optional power‑saving switch.
✓Gigabit Ethernet port praised for delivering wired speeds that match the modem’s maximum throughput.

Criticized by Experts

✗Cox notes the SB6121 is functional but limited to about 50 Mbps on their network, recommending a DOCSIS 3.1 upgrade.
✗Professional commentary points out the lack of Wi‑Fi and limited channel count make it unsuitable for future‑proofing.

From User Reviews

Users Love

✓Customers appreciate the straightforward plug‑and‑play setup and reliable connection for basic cable internet.
✓Users report the modem works well with a variety of operating systems, including Windows, macOS, and UNIX.
✓Energy‑saving switch is valued by budget‑conscious households that want to reduce electricity usage.

Users Complain About

✗Everyday users mention the need to purchase a separate router because the modem provides no wireless capability.
✗Feedback indicates the device struggles to achieve advertised speeds on plans exceeding 100 Mbps.
✗Some buyers are concerned about refurbished units potentially delivering lower performance.

Expert Opinion

Professional sources and manufacturer literature praise the SB6121 for its solid 4×4 DOCSIS 3.0 channel bonding, energy‑efficient design, and reliable wired performance with major cable providers. However, reviewers note that the modem’s DOCSIS 3.0 platform and limited channel count are insufficient for today’s high‑speed plans, and they recommend upgrading to a DOCSIS 3.1 model for future‑proofing.

What Users Say

Typical users find the SB6121 easy to install and reliable for basic internet needs, especially when paired with a separate router for Wi‑Fi. Common complaints revolve around its inability to keep up with faster broadband packages, the absence of built‑in wireless, and concerns over refurbished units.

Common Complaints

Limited downstream channel count leading to lower real‑world speeds on high‑tier plans, lack of Wi‑Fi requiring an extra router, and the prevalence of refurbished units that may underperform.

How It Compares

vs. Arris SB6141

Advantages

✓Double the downstream channels (8x4) enabling speeds over 300 Mbps, better for higher‑speed plans.
✓Same Gigabit Ethernet port while offering higher throughput capacity.

Disadvantages

✗Typically higher price point than the SB6121, which may be unnecessary for basic plans.
✗May not provide the same ENERGY STAR power‑saving features as the SB6121.

Choose the SB6121 for budget‑friendly, mid‑tier plans; opt for the SB6141 when you need higher downstream capacity for faster internet packages.

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