CenturyLink C4000LG CenturyLink Modem by GreenWave (Renewed)
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AI Verdict
This is a renewed CenturyLink C4000LG modem/router with Wi-Fi 6 and 3 Gbps theoretical speed, best for single-line DSL users on a budget.
Regret Score™
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Amazon rating vs actual quality
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Pros
- Supports Wi-Fi 6 (802.11ax) with 2-stream connectivity for up to 3 Gbps theoretical wireless speed
- Includes 1 DSL port compatible with ADSL or VDSL profiles up to 17a
- Features a dual-core 0.8 GHz processor for network performance
- Offers four Gigabit Ethernet LAN ports for wired connections
- Incorporates security features like an advanced firewall and WPA2 encryption
- Supports 160MHz channel bandwidth and 1024-QAM for increased data rates
Cons
- Many users report it being buggy and inferior in hardware compared to other CenturyLink models like the C4000XG or C3000A/Z
- Not suitable for bonded DSL lines; specifically designed for single-line DSL
- Users frequently experience slow speeds, disconnects, and a glitchy web interface
- Hardware specifications (0.8 GHz CPU, 512MB Flash/SDRAM) are less robust than the C4000XG
- Some users received it mistakenly for fiber service or experienced hardware failures shortly after purchase
Dimension Scores
The modem offers theoretical 3 Gbps Wi-Fi 6 speeds and 160MHz channel support, but user reports indicate actual throughput is often inconsistent and lower than expected, with frequent disconnects.
Numerous user complaints highlight the C4000LG as 'buggy' and 'inferior,' with reports of slow speeds, disconnects, UI crashes, and hardware failures, indicating poor reliability.
It features an intuitive web-based setup wizard and Smart Wizard software, but the user interface is frequently described as 'glitchy' and prone to crashing, hindering effective management.
The modem includes an advanced firewall, WPA2 encryption, MAC address filtering, parental controls, and guest network options, providing a standard set of security functionalities.
Best For
- Single-line CenturyLink DSL internet connections up to VDSL2 17a profile
- Users needing a modem/router combo with Wi-Fi 6 on a strict budget
- Basic internet usage like browsing and email in smaller homes
- Replacing an older, failing single-line DSL modem/router
Not Recommended For
- CenturyLink bonded DSL service or fiber optic connections (unless specifically GPON compatible and confirmed by ISP)
- Users requiring consistent high speeds for demanding applications like 4K streaming or online gaming
- Anyone expecting a stable, bug-free user experience without troubleshooting
- Large homes or environments with many connected devices needing expansive Wi-Fi coverage
Watch Out For
- The 0.8 GHz dual-core processor and 512MB memory are less powerful than the C4000XG, potentially leading to performance bottlenecks.
- Multiple user reports indicate a 'glitchy' user interface that crashes when making setting changes.
- Some users experienced reduced actual speeds compared to older modem models, even with higher theoretical Wi-Fi 6 speeds.
- There are recurring complaints of the device failing or becoming unresponsive, sometimes within weeks of use, displaying solid red lights.
- CenturyLink support sometimes sends this model incorrectly for fiber or bonded DSL, leading to compatibility issues and frustration.
Full Specifications
| ASIN | B08N5C139T |
| Brand | CenturyLink |
| Item Weight | 2.66 pounds |
| Manufacturer | GREENWAVE |
| Compatible Devices | Laptop |
| Product Dimensions | 5.5 x 5.5 x 8.1 inches |
| Connectivity Technology | LAN, WLAN |
| Internet service provider | centurylink |
What Buyers Say
The most surprising finding from user feedback is the consistent advice to avoid the C4000LG, with many suggesting older models like the C3000A/Z or the C4000XG are more stable and perform better. Users frequently report issues like the modem dropping connections, the web interface being unresponsive or crashing, and overall slower speeds than advertised or experienced with previous devices. There are also multiple instances of the device failing completely, sometimes within weeks of purchase, displaying a solid red light. The confusion around its compatibility for different CenturyLink services (DSL vs. fiber, single vs. bonded) also causes significant frustration for buyers.
“Man, this C4000LG is a headache, keeps dropping my connection and the settings page just freezes up, wish I stuck with my old C3000A, this 'upgrade' is a downgrade.”
Common Praise
- Supports Wi-Fi 6 technology
- Includes four Gigabit Ethernet ports
- Compatible with single-line ADSL/VDSL up to 17a
- Amazon Renewed product is inspected and tested to look like new
Common Complaints
- Frequent disconnects and unstable internet connection
- Slower actual speeds compared to older modems or expectations
- Glitchy and crashing web-based user interface
- Hardware failures, often indicated by a solid red light
- Not suitable for bonded DSL lines, causing compatibility issues for some users
- Considered 'buggy and inferior in hardware' by many users
Ownership Tips
- Expect to frequently restart the modem to restore connection stability.
- The web interface might be frustrating to use for configuration changes due to crashes.
- You might experience slower real-world speeds than your internet plan or older modems provided.
- Be prepared for potential hardware failure, as several users reported the device dying prematurely.
- Confirm your CenturyLink service type (single-line DSL, bonded DSL, fiber) to ensure this modem is even technically appropriate before purchasing.
Frequently Asked Questions
Is the CenturyLink C4000LG compatible with bonded DSL service?
No, the C4000LG is designed for single-line DSL service (ADSL or VDSL up to 17a profile) and is not recommended for bonded DSL lines.
What Wi-Fi standard does the C4000LG support?
It supports Wi-Fi 6 (802.11ax) with 2-stream connectivity, offering theoretical speeds up to 3 Gbps.
Does this modem have Gigabit Ethernet ports?
Yes, the C4000LG includes four Gigabit Ethernet LAN ports for wired connections.
Can I use the C4000LG with CenturyLink fiber internet?
While it is technically compatible with fiber optic GPON, many users report being sent this modem incorrectly for fiber, and its performance for fiber may not be optimal compared to dedicated fiber equipment.
Are there known issues with the C4000LG's software or stability?
Yes, many users have reported the C4000LG's user interface as 'glitchy' and prone to crashing, and there are frequent complaints about general instability, disconnects, and hardware failures.
Buying Guide
When you're looking at a modem/router combo like this, you need to understand it's the gateway for your internet. It takes the signal from your internet provider (in this case, DSL) and converts it into a network you can use via Wi-Fi or Ethernet cables. The 'renewed' part means it's been checked out, but it's still a used device. For DSL, compatibility with your specific line type (ADSL, VDSL, bonded) is crucial, and getting the wrong one means no internet.
3 Gbps Speed (600+2400 Mbps)
This number tells you the theoretical maximum speed the Wi-Fi can handle. The '600+2400 Mbps' breaks it down by frequency band (2.4GHz and 5GHz). Higher numbers mean faster data transfer over Wi-Fi, but your actual internet speed will be limited by your CenturyLink plan.
1 DSL Port (ADSL/VDSL up to 17a)
This is the port where your phone line (DSL) connects. 'ADSL/VDSL up to 17a' specifies the types of DSL technology it supports. If your CenturyLink service uses a different profile or is 'bonded' (two phone lines), this modem won't work correctly, regardless of its other features.
Networking Optimized Dual-Core Processor
Think of this as the modem's brain. A more powerful processor can handle more simultaneous connections and data traffic without slowing down. A 0.8 GHz dual-core is entry-level for modern networking devices, which can impact performance under heavy load.
Wi-Fi 6 (802.11ax)
This is the latest generation of Wi-Fi technology. It's designed to be faster and more efficient, especially in environments with many connected devices. However, you'll only get the full benefits if your devices (laptops, phones) also support Wi-Fi 6.
Alternatives
If this modem doesn't fit, look for a CenturyLink-approved modem/router that explicitly supports your specific DSL line type (e.g., bonded VDSL2) or a dedicated fiber ONT if you have fiber service, and consider models with a 1 GHz or faster dual-core processor and at least 1GB of RAM for better stability.
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