I have been thinking about upgrading my Linksys BEFCMU10 Ver. 2 DOCSIS 2.0 cable modem to a new DOCSIS 3.0 model, but I have some questions and concerns.

I have been looking at the following DOCSIS 3.0 modems:

- Motorola SB6120
- Motorola SB6121
- Zoom 5341
- uBee DDM3513

Has anyone heard anything good or bad about any of the models above?
Do you own any of the above cable modems and what do you think of it?

I currently live in the Cleveland, Ohio area and have Time Warner Cable (Road Runner) service. Some of the things I have read online make it sounds like I won't be able to use a DOCSIS 3.0 cable modem with Time Warner unless I upgrade my plan. Others make it sound like even then TWC won't let you use your own DOCSIS 3.0 modem.

Have any of you ran into this problem?
Do any of you own your cable modem?

I would like to get a new cable modem, since my current one is probably close to 10 years old and it seems to go offline at least once or twice a day lately. I have to unplug the modem and then plug it back in to get it working again. This is very frustrating when I am working on a client's website and upload or downloading project files.

It is also frustrating when watching a movie on Netflix or downloading an PS3 or Xbox 360 game.

Does your cable modem go offline regularly?

It would be cool if I could get higher speeds with a DOCSIS 3.0 modem, but I would really like to just be able to stay online throughout the day without having to reset the cable modem all the time. I would like to buy a DOCSIS 3.0 modem instead of a 2.0 one even if I only use it for 2.0 for now. I would rather have the latest technology instead of spending about the same amount for an older standard.

What are your thoughts on DOCSIS 3.0 cable modems, your cable company, and using your own cable modem?

Any help or advice on this topic would be appreciated.

I wish you luck dealing with Time Warner. A few people I know tried to do the same over the last few months. For whatever reason, at least in the Akron area, Time Warner is really making it hard to use your own modem ... which is strange considering we have OBEN which requires just that. Anyway, two people eventually gave up and just took the modem Time Warner gives you, the other spent 5 weeks escalating calls and eventually was allowed to use his own (I will find out the model for you). All are happy and from some crude benchmarks actually get about the same performance from the modems.

Just a side note, 3 of us noticed a bigger performance increase by buying a new router than replacing the modems. The old WRT54G's just can't handle the throughput available now.

I bought a new Apple AirPort Extreme wireless router last year and I don't think and hope the router is not the problem. When I get disconnected the modem's "Online" light starts flashing and I lose all Internet access on all devices in the house.

It seems like the old modem cannot handle all the traffic we are sending through it. The Linksys cable modem disconnects more often when I am watching Netflix or surfing the web and searching for things and also trying to FTP or do other things at the same time.

I have multiple computers or devices connected to the Internet almost all the time. I also use CrashPlan for online backup, so I am uploading files throughout the day from my main computer as I add new files.

I am worried about buying a new modem and not being able to use it or TWC telling me I need to upgrade my plan to use it. I also don't want to lose speed, since I am getting 14.5Mbps download and 0.95Mbps upload when I test on http://Speedtest.net and I am happy with those numbers.

Should I expect to be disconnected regularly from the Internet? Is this normal and should I just learn to live with it?

that's odd that they would give you such a hard time about adding your own modem.
do they charge modem rental fees? If not I would just get them to give you a d3 modem they will work with current plans as we've been using them for about 2 years now.. I mainly install the ubee ones and I'd recommend the motorola brand as they tend to have fewer fail rates.

TWC used to charge you to rent the modem back when I first got cable modem service. That is why I bought my own, since I didn't want to pay $7 a month when I could buy one for $100 and keep it for 5 or 10 years. I don't know if they charge for modems anymore.

It sounds like Motorola is best brand, but do cable companies only allow certain brands or modems on their network?

I heard that TWC was using uBee modems somewhere on the Internet when I searched, so would it be better to get one they use or does it not really matter?

I am guessing D3 means DOCSIS 3.0, but I am just making sure. Is this correct?

Most cable companies are pretty open about supported modems just make sure you buy something brand new and DOCSIS 3 I'd go Moto though!

Do you know of any advantage or disadvantage buying the Motorola SB6120 over the SB6121?

The SB6120 is cheaper and seems to have the same features as the newer SB6121. I also heard the SB6121 runs hotter to touch.

Time Warner does not charge for cable modem rental anymore. They do charge if you get the wireless version, but since you have the Apple Router it won't be an issue.

Time Warner is also using the Motorola SB Modems, so you might just get the same one without buying it. My friend said if you are to use your own to try and get in touch with the National Help desk. Again, at least in Akron, the local people would not allow it.

PS: I got 28.5Mbps download and 0.91Mbps upload on speedtest.net just now.

That's pretty amazing that they say they do not allow it. You'd think the FCC would be all over them for that lol I guess that's why they don't charge for them in order to bypass that.