Home > Consumer Reviews > Linksys BEFCMU10 Ethernet Cable Modem

First I need to thank all of you guys who gave the Linksys cable modem 4 and 5 stars. If it had not been for your reviews I would have sent this great modem back to Amazon.

I spent 6 hours trying to get this modem working, getting help from 4 different techs at AT&T. They told me that this modem was bad and that the cable light needed to stay on and that the Linksys modem would not register with their system. They told me I needed to send it back and get another one. {ALL FALSE} So finally I told them to connect my (their) old modem back up. Their modem worked fine.

As I was getting ready to pack my new Linksys modem up to send it back to Amazon. I decided to try it one more time. Following the exact sequence they used to connect their modem. And would you believe it? It works!!!

My problems:
1. bad tech support.
2. must remove router to register modem.
3. given wrong registration address. (MOST IMPORTANT)
4. computer must be turned off before you turn on modem.

Fool proof procedure to be up and running in 10 minutes:

1. Turn computer off.
2. If you have a router, take it out of the loop. connect directly from your computer to the modem thru the ethernet port.
3. Connect the cable.
4. turn on power to the Linksys modem, allow it to boot up.
5. turn on your computer
6. go to the registration page to register your modem. You MUST do this twice, for some reason it does not work the first time. MAKE SURE YOU GET THE RIGHT ADDRESS FROM AT&T. They failed to tell me I needed to use "https://" instead of "http://" it won't work without the "s"
enter your account # and registration #.
7. You should be working. Reconnect your router.

I get my cable modem service through ATT broadband. I have my home networked using a Linksys router, which I consider to be an excellent product. I'd been monitoring the price of cable modems and when I saw the Linksys cable modem for less than $100 (with rebate), I decided to make the purchase and save $10 a month from ATT. The installation couldn't have been easier. I powered down the PC, removed the RCA CM and connected the new Linksys. I powered up, started my browser (IE) and was immediately redirected to an ATT website which asked me for my account number and registration number (last 9 numbers of the account number). I entered them and was forwarded to a page to register the Linksys CM's MAC address, which was automatically placed into the box. I clicked OK and, voila! Done! The next day I returned the leased RCA CM to my local ATT center and they (I hope) adjusted my monthly bill. ATT said they would pick up my CM but that carried a $49 charge.

Prior to the purchase, I called the ATT support center. This proved to be an absolute waste of time. I was on hold for 20 minutes and then the rep was not very helpful. So I started a chat session with another ATT rep and got the exact information I needed. And it worked just as she said it would. And, I was immediately connected to a rep as opposed to the telephone call where I was placed on hold. My advice - skip the phone call - start a chat session instead. More advice - you CANNOT go wrong with Linksys!

After discovering our DSL connection had been degraded by new construction in the area it was time to try cable. We were near the limit for DSL any way but then, after some new construction increased our loop length, our DSL service was downgraded to 384k (download). A quick check of monthly service fees and it was clear cable modem service was a better deal. For us, cable service is $20 a month less and, as it turns out, the speed of cable is almost 10x faster.

Like other reviewers I decided to purchase a modem instead of rent. I checked the Comcast list of approved modems and noticed that this Linksys BEFCMU10 was on the list. I made sure to purchase a V3 model. I liked the idea of being able to stack it with my Linksys wireless router. I read elsewhere that some have had compatibility problems with other Linksys products but I had no such problems.

After calling Comcast to give them the MAC address and the serial number (both clearly printed on the modem's underside label) I was up and running. I had zero problems getting this modem connected and working.

I elected to self install with Comcast which means they send you a kit that contains a splitter to add to your home's cable input and a couple of cables. It is important with all cable modems to provide them with the strongest signal strength possible. This means you need to install the modem with nothing else "ahead" of it on the cable coming into your house. This means you should install the splitter as close to the source (where it comes into your house) as possible. If signal strength becomes an issue you can purchase signal amplifiers to boost your video signal to your TV's, etc., but a decent one with adjustable gain costs as much or more than this modem.

With a good strong signal this modem works perfectly. It stacks neatly onto an existing Linksys router too. The build quality is typical Linksys which I consider quite good for comsumer level gear. My only regret is that we did not switch sooner.

Make sure you get a BEFCMU10 v3 ***NOT*** the v2. There is a well-document problem with the v2 units below a certain firmware level, and Linksys refuses to acknowledge the problem. Search for "BEFCMU10 lockup" in your favorite search engine. Worse, since it's a DOCSIS cable modem, it has to receive updates from your cable provider and many of them refuse to acknowledge this, telling you to talk to the hardware vendor.

This unit works well unless you exceed some traffic threshold. If you use this unit with a broadband router and have multiple computers in your house, you use peer-to-peer file sharing programs, you try to download email while updating your computer, etc., the modem will lock up and need to be rebooted.

Some posters online have been able to get both Linksys and their cable provider to coorperate and get them the updated firmware, but many others can't. I got my cable provider to acknowledge that they needed to provide me with the firmware, but Linksys refused to acknowledge there was a problem, even when pointing out online accounts of this problem and them successfully getting updates.

Works great:
1) Get your Account # ready, and registration # (last 9 digits of Acct #)
2) Turn computer off
3) If you have a router, take it out of the loop, connect directly from computer to the modem thru ethernet port
4) Connect cables
5) Turn on cable modem, let boot up
6) Turn on computer
7) Goto registration page (you probably need to call AT&T Broadband for this info)
8) You are good to go... turn off computer, insert router (if you have one)