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Sagemcom F@ST 3864AC

Sagemcom F@ST 3864AC

1.9 from 59 reviews · View Statistics
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  • Build Quality
    5.0 (3)
  • Value for Money
    5.0 (3)
  • Number of Connected Devices 11.333 devices
  • Ease of Setup
    5.0 (3)
  • Reliability
    4.7 (3)
  • Wi-Fi Range
    4.0 (3)
  • 6 reviews

Does the basic functionality fine


Purchased in January 2018.

Build Quality
Value for Money
Bharat Ratan S.
Bharat Ratan S.Greater Melbourne (Outer), VIC
  • Verified

Nice modem with adaptability and good life.


Nice modem but have to reset it sometimes. It has been working fine for more than a year (2 yrs of which I have been with Optus) though I had an option to upgrade to a new modem but I did not as it has been working fine. The Status LEDs are pretty accurate and help me to understand my connectivity.

Purchased in May 2017.

Build Quality
Value for Money

Other Modems


davebGreater Melbourne (Outer), VIC

Works fine for me . . .


Changed from Optus-Cable to Optus-NBN-HFC 7 weeks ago, and got delivered one of these routers. Simply connected to Arris modem as installed by NBN, then personalised WiFi psw etc .

Has worked 100% for me (including 5GHz WiFi) with touch-wood, no lockups / dropouts (so far). The version is 3684 v3 HP - so maybe in this latest firmware, all the bugs that have upset others have been removed . . .

Purchased in March 2019.

Build Quality
Value for Money

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JimmySouth East Queensland, QLD
  • 17 reviews
  • Verified

Generally good, sometimes needs a restart


This modem came for free with my Optus cable internet connection and have been using for 12 months now.

Overall, I'm pretty happy with it. I have not experienced dropouts, although I have had wifi speed drop to almost 0 a few times, requiring a restart of modem and router which fixed the issue.

Date PurchasedJan 2018
  • 5 reviews
  • Verified

Great Modem - Easy Install


Arrived on time promptly form Optus, set up was very easy also. Sleek modern look also. The connection has been great, doesn't drop out at all. Perfect size and easy to hide in plain sight. Optus has done a great job with the nbn connection also, couldn't be happier. Entire process was smoothe and communication was great also. Answered all our queries about modem/nbn and helped us understand the best possible bundle for our new home.

Date PurchasedJuly 2018
  • 3 reviews

Good allrounder


Modem is an upgrade from previous model.
With previous model went through 2 of them in 6 months. This one, touch wood, has been great with no issues.
At least this model has dual band where the previous model did not and seems to be better made.
Also has quick and easy setup for dummies.

Date PurchasedSept 2017
Greg R
Greg RWollongong
  • 30 reviews
  • Verified

Fast and reliable


My previous NBN modem was a single band 2.4ghz. This new version from Optus has dual band 2.4ghz and 5ghz. The 5ghz is lightning fast and having dual band allows connection on wi-fi or 32 devices (previously 16). The speed directly from the ethernet ports to my fetch tv box and the x-box is awesome. So far very pleased with the reliability and speeds.

Date PurchasedAug 2017

Questions & Answers

Ken B.
Ken B.asked

Will this work for NBN

1 answer

It was standard issue modem around two years ago with Optus NBN. It will work with any provider as it is a generic modem. Ethernet output cable from NBN ARRIS box goes as input this modem. Note the NBN coax cable does not go into this modem.


my wifi extender WN2500RPv2 no longer works after the sagecom nbn modem was installed. Tried resetting via WSP and web but does not fix the problem. Ios device also cannot pick up connection with extender and keeps giving wrong IP address. Do i need to configure something on Sagecom modem ? Do i need to add MAC address etc ?

4 answers

Is the Sagemcom new? If so, I think you have to configure everything to suit. I have a Sagemcom and its wifi is useless - keeps dropping out. I still use the Sagemcom for the phone landline but I hardwire another router from for my wifi


Thanks for reply. Yes, Sagecom modem is new; was provided as part of change from cable to NBN and was set up by service provider. What do I need to change in the configuration ?


Along with the Segemcom modem, I am using Netgear R6400 AC1750 Smart WiFi router, there is no issues so far.


does this router have voip capability

1 answer

Yes. I plug my landline into it and seems to work ok. Just the wifi part isn’t much good

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CategoryRouters and Modems
Product TypeModem and Router
Wi-Fi Type802.11 b, 802.11 g, 802.11 n and 802.11 ac
Band TypeDual Band
Ethernet Ports4
USB Ports2

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