ARRIS DG3450 DOCSIS 3.1 Modem Router Combo | Xfinity, Cox, Spectrum

The renewed ARRIS DG3450 is a DOCSIS 3.1 cable modem router combo built for gigabit internet, heavy streaming, and busy multi-device homes. One all-in-one gateway replaces both your rented modem and your WiFi router, ends the monthly equipment fee, and adds MoCA 2.0 support for stable whole-home coax networking. Every unit is tested, restored, and shipped fast from US warehouses, backed by our 90-day full coverage warranty.

Key Takeaways

• DOCSIS 3.1 gigabit-capable all-in-one modem and WiFi router, backward-compatible with DOCSIS 3.0.
• Approved for Xfinity, Cox, and Spectrum cable internet, and deployed by regional providers such as TDS Telecom (confirm with your ISP's approved device list).
• Replaces rented gateway equipment, which can save $120 to $180 per year depending on your provider.
• Renewed and tested, covered by a 90-day full coverage warranty and USA-based customer service.

Is the ARRIS DG3450 Compatible with My Internet Provider?

The ARRIS DG3450 is approved on most major cable internet providers, including Xfinity (Comcast), Cox Communications, and Spectrum. It is also used by regional cable providers such as TDS Telecom. Because it supports both DOCSIS 3.1 and DOCSIS 3.0, it works on standard and gigabit cable plans alike. For provider-specific setup help, see our Xfinity activation guide, Spectrum activation guide, or Cox activation guide.

The DG3450 does not work with DSL, fiber (Verizon Fios, AT&T Fiber, Google Fiber), or fixed wireless internet. Before activating, always confirm this model is listed on your provider's approved device page and matches your speed tier.

Modem Router Combo vs Separate Modem and Router

A gateway like the DG3450 gives you one device, one power outlet, and one setup process, which is the simplest path online for most households. A separate modem and router cost more up front and take up more space, but let you upgrade the WiFi side independently later. If you want simplicity and solid dual-band coverage on a plan up to 1 Gbps, the DG3450 handles both jobs. If you already own a router or mesh system you love, you can still use it: connect it to a LAN port and disable the DG3450's built-in WiFi. For standalone alternatives, see our Best DOCSIS 3.1 Modems of 2026 roundup.

ARRIS DG3450 Specs at a Glance

Save on Modem Rental Fees

Xfinity, Cox, and Spectrum all supply gateway equipment, and where a rental fee applies it typically runs $10 to $15 per month. At $180 a year on the high end, this renewed DG3450 pays for itself in about six months, and everything after that is savings. Some providers have reduced or bundled their fees, so check your current bill to see exactly what you are paying. If your rented gateway is aging or acting up, our guide on how long modems last covers the signs it is time to replace it.

What's in the Box

• ARRIS DG3450 cable modem router combo (Renewed)
• Power adapter
• Ethernet cable
• Quick start guide

Coaxial cable, MoCA adapters, and splitters are not included and are typically supplied by your ISP or sold separately.

How to Set Up the ARRIS DG3450

1. Connect the DG3450 to your active cable wall outlet using a coaxial cable.
2. Plug in the power adapter and wait for the front lights to stabilize (about 5 to 10 minutes on first boot).
3. Connect a computer or phone to the default WiFi network printed on the device label, or plug into a LAN port with the included Ethernet cable.
4. Call your internet provider or use their self-activation portal to register the modem's MAC address.
5. Once activation completes, sign in to the gateway's admin page to customize your WiFi name and password.

If the lights keep blinking or the online indicator never goes solid, our Arris modem lights guide explains what each light means and how to fix common connection issues.

Why Buy the ARRIS DG3450 from ModemGuides

• 90-day full coverage warranty on every modem we sell, including this renewed DG3450.
• USA-based customer service and tech support staffed by people who actually know networking gear, not a generic call center.
• Fast shipping from US warehouses across the country, so most orders arrive in 1 to 3 business days with minimal handling time.
• Curated, ISP-compatible inventory: we only stock modems and routers that are approved on real cable plans, with clear compatibility notes on every listing.
• Setup and troubleshooting guides available across ModemGuides.com to help you get online without the runaround.
• Small US business that puts customer experience first, with real humans answering your questions.

ARRIS DG3450 Frequently Asked Questions

Will the ARRIS DG3450 work with Xfinity gigabit plans?

Yes. The DG3450 is DOCSIS 3.1 and supports Xfinity gigabit plans where it appears on Xfinity's approved modem list. It also works on lower-speed Xfinity tiers thanks to DOCSIS 3.0 backward compatibility.

Is the ARRIS DG3450 a modem and a router?

Yes. The DG3450 is a modem router combo, also called a gateway. It includes a built-in dual-band WiFi router, so you do not need a separate router unless you want to add a mesh system or use your own preferred router.

Does the ARRIS DG3450 work with TDS Telecom?

The DG3450 is a gateway model deployed by TDS Telecom on its cable internet plans. If you are a TDS customer, confirm the DG3450 is approved for your specific plan and area before activating.

Can I use my own router with the DG3450?

Yes. You can disable the built-in WiFi and connect your own router or mesh system to one of the gigabit LAN ports. Bridge mode availability depends on your ISP's firmware configuration. For pairing options, see our Best WiFi Routers for Gigabit Internet guide.

What is MoCA 2.0 and do I need it?

MoCA 2.0 lets you run a high-speed wired network over your existing coaxial cable lines, which is useful for rooms where WiFi is weak. You only need MoCA if you plan to hardwire devices over coax, and you will need a MoCA 2.0 adapter at the other end.

Does the DG3450 support WiFi 6?

No. The DG3450 uses 802.11ac (WiFi 5) Wave 2 dual-band WiFi. If you need WiFi 6 or WiFi 6E, pair the DG3450 in bridge mode with a WiFi 6 router or mesh system.

What do the lights on the ARRIS DG3450 mean?

Blinking lights during boot are normal for the first 5 to 10 minutes. After activation, the power and online lights should be solid. Persistent blinking usually points to a coax signal issue or an activation that has not completed, and our Arris modem lights guide walks through the fixes.

Is this DG3450 new or refurbished?

This DG3450 is a Renewed (refurbished) unit. Each gateway is professionally inspected, tested, and restored to working condition, then backed by a 90-day full coverage warranty.

How fast will my modem arrive?

Most orders ship the same or next business day from our nearest US warehouse and arrive in 1 to 3 business days. You will receive tracking as soon as your order is on the way.

What happens if the modem stops working?

If anything goes wrong within the first 90 days, contact our USA-based support team and we will troubleshoot, replace, or refund. We stand behind every modem we ship.