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Friday, February 13th, 2026 12:14 AM

Netgear CM3000 Partial Upstream OFDMA Lock (Only One Channel) After Tech Reprovision & Factory Reset – Upload Capped ~36-67 Mbps on Gigabit

I have a Netgear Nighthawk CM3000 cable modem on the Gigabit x2 plan (2000 Mbps down / 250 Mbps up). After a field tech came out and attempted reprovisioning, plus multiple chat/phone attempts and a full factory reset on the modem, the upstream is still only partially provisioned.

Current modem status (from 192.168.100.1 > Cable Connection):

•  Downstream: 32 QAM256 channels fully locked + 2 OFDM channels locked (good power/SNR, zero uncorrectables).

•  Upstream Bonded Channels: 4 ATDMA channels locked (frequencies around 16-35 MHz, power ~49.5 dBmV).

•  Upstream OFDMA Channels: Only one channel locked (profile 12,13 at ~36.2 MHz, power ~43-44 dBmV). The second channel is Not Locked (0 Hz / 0 dBmV).

Speeds are inconsistent:

•  iPhone on Wi-Fi 6E (6 GHz band) occasionally bursts to ~1200 down / ~290 up (Ookla).

•  MacBook Air wired/wireless typically gets ~300 down / ~36-67 up.

•  Direct Ethernet to modem (bypassing router): ~550 down / ~20 up.

This matches the partial upstream OFDMA lock—legacy ATDMA fallback caps upload around 35-40 Mbps consistently, with occasional bursts when the single OFDMA channel is utilized.

The modem is on the Xfinity approved list for multi-gig with mid/high-split enhanced upload. Signals are clean (downstream power 0 to +3 dBmV, upstream ~49 dBmV), no critical errors in event log, and the modem reboots cleanly after reset.

Multiple reprovisions (including by field tech) keep sending an incomplete bootfile/config that doesn’t fully lock both upstream OFDMA channels or apply the complete Next Gen Speed profile.

Please escalate this to Tier 2 provisioning or network engineering so they can:

•  Verify the current bootfile assigned to this modem.

•  Manually push the correct Next Gen/enhanced upload bootfile/CMTS config to enable full upstream OFDMA bonding (both channels locked).

Happy to DM account details, modem MAC (last 4 digits if needed), or full screenshots for privacy. Thanks for the help—really need this resolved.

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2.2K Messages

2 hours ago

Hello @OO7Goofy, Thanks so much for taking a moment out of your day to leave a post on our community forum and we would be happy to help. If you could send our team a direct message with your full name, the name listed on the account (if different), and the service address associated with your account, I'd be more than happy to look into this for you. To send a Direct Message, please click on the chat icon in the top-right corner of the screen, next to the bell icon, and then type or select "Xfinity Support" to initiate a direct message.

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