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Black Micro USB Ethernet adapter with integrated cable and RJ45 port

Cable Matters 3940 Micro USB Ethernet Adapter 300 Mbps

SKU CH-G9FC-7A6A4 MPN 3940

Adds a wired 300 Mbps network link to Fire TV Stick, Chromecast or Google Home Mini via Micro USB

  • ColorBlack
  • Weight0.091 kilograms
  • Stable wired streaming eliminates Wi-Fi buffering
  • Up to 300 Mbps Ethernet speed exceeds 100 Mbps Fast Ethernet
  • Plug-and-play setup requires no drivers or software
  • 3-foot USB power cable connects to wall charger
  • Compatible with Fire TV Stick, Chromecast and Google Home Mini

Micro USB to Wired Ethernet Adapter

The Cable Matters 3940 adds a wired RJ45 network port to streaming sticks that only have a Micro USB socket. It targets owners of Fire TV Stick, Fire TV Cube, Chromecast generations one to three, Chromecast Ultra and Google Home Mini who suffer from wireless buffering. The adapter draws power from an external USB wall charger rather than the TV port.

Check Device Compatibility and Power Source

Verify that your streamer appears in the supported list; Fire TV first generation, all Roku models, smartphones and tablets will not work. A USB wall charger must be available because the TV's own USB port cannot supply enough current. An RJ45 patch cable long enough to reach your router or modem is also required before you begin.

Sustained Streaming Over Long Sessions

Wired 10/100 Ethernet keeps latency low and throughput steady during multi-hour 4K playback, avoiding the drops that plague congested Wi-Fi. The 300 Mbps ceiling is well above typical streaming bit-rates, so the link stays saturated without thermal throttling. Continuous power from the wall adapter prevents the voltage sags that cause disconnects on TV-powered dongles.

Highlights

  • Stable wired streaming eliminates Wi-Fi buffering
  • Up to 300 Mbps Ethernet speed exceeds 100 Mbps Fast Ethernet
  • Plug-and-play setup requires no drivers or software
  • 3-foot USB power cable connects to wall charger
  • Compatible with Fire TV Stick, Chromecast and Google Home Mini

Specifications

BrandCable Matters
Model202053
ColorBlack
Weight0.091 kilograms

Questions about this item

Does the box include the RJ45 patch cable and USB wall charger needed for setup?

The adapter comes with a 3-foot USB power cable. You must supply the RJ45 patch cable and a USB wall charger yourself.

Which streaming sticks work with model 3940 according to the compatibility notes?

The adapter supports Fire TV Stick, Fire TV Cube, Google Chromecast generations 1 through 3 up to August 2020, and Google Home Mini. Roku devices and smartphones are not supported.

What does the 300 Mbps headline speed mean for streaming over a typical home router?

The adapter delivers up to 300 Mbps wired throughput, which is three times faster than 100 Mbps Fast Ethernet and provides a stable link that removes Wi-Fi buffering during video playback.

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