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About to move and going to stop leasing from Comcast, have not shopped for a separate modem in about 8 years due to various circumstances and wondering what the landscape looks like these days, any recommendations or recommended reading?

http://mydeviceinfo.xfinity.com/ is a great place to start.

Wirecutter Cable Modem Reccomendation

I had this one, and it worked like a charm at 90-100mbps. Unfortunately, it got lost in a lightning hit. This time I bought a Netgear modem/router hybrid to save space and clean up cabling. Both worked very well with Comcast.

Thanks for the responses, reading around the SB6141 looks great for what I'd be using it for.

Prion wrote:

Thanks for the responses, reading around the SB6141 looks great for what I'd be using it for.

Make sure its white. That is the consumer one and are retail. And thus are warrantied by Motorola. The black SB6141 are refurbs and are usually sold to ISPs and are warrantied by the ISP.

One small complaint I had about the SB6141 - the LEDs were insanely bright. Easily the brightest I have seen in a consumer electronics device and by far the brightest thing in my bedroom at night. I liked the device a lot and was not planning to replace it until the lightning killed it, but I can't say I miss that aspect of it at all - the Netgear device is very muted by comparison.

bwoodring wrote:

One small complaint I had about the SB6141 - the LEDs were insanely bright. Easily the brightest I have seen in a consumer electronics device and by far the brightest thing in my bedroom at night. I liked the device a lot and was not planning to replace it until the lightning killed it, but I can't say I miss that aspect of it at all - the Netgear device is very muted by comparison.

It is kinda like that on all their gear (the Moto Surfboards). I have a 6183 and it's the same. Tape tape tape.

Don't get the SB6141, it only has 8 downstream and 4 upstream channels (8x4), the LEDs are insanely bright, and people have had overheating problems.

You'll almost always see a speed boost from a 16x4 or 24x8 modem. I went with the Netgear CM500 (16x4). It sits in my living room and has very nice faint LEDs. I pay for 105mbps on Comcast and now get 180mbps on that modem. The 24x8s aren't really cost-effective but they might be faster.

As a sidenote, Comcast is rolling out DOCSIS 3.1 in the next 18 months or so, so be prepared to buy/rent another modem to unlock gigabit-class speeds if you pay for fast internet already.

FWIW, DTD, that isn't necessarily about just the modem "being fast." Comcast clearly has not provisioned it properly to give you the speed you pay for. Which is awesome for you, but is also VVVVVVVVVVVVYMMV.

Bought a SB6141 last month. Bright led lights and rock solid so far at 60/5. For the speeds I need, it's perfect for taking that pesky $10/mo lease charge away

I got the D-Link DCM-301 DOCSIS 3.0 Cable Modem about a year ago. It's more stable the the cable company. In fact, I don't remember doing a reboot where that actually was the fix.

So, there ya go.

Prion wrote:

Thanks for the responses, reading around the SB6141 looks great for what I'd be using it for.

It's a good modem. It is probably all you will need.... that said if you currently am or are thinking you might pay for higher bandwidth tiers in the future you may want to pay the $20 difference and bump up one level to the SB6183. The difference is 8x4 vs 16x4 bonding channels, so the 6183 theoretically supports 76MB/s download speeds. The 6141 is capped at 38Mb/s. Aside from that more downstream channels helps keep your bandwidth stable in congested cable areas.

Whichever you get, don't buy a refurb model. As others have said the refurbs tend to be previously used by ISPs. I personally use the SB6183 and would recommend it!

https://www.amazon.com/TP-LINK-Certifie ... B01CVOLKKQ

I have this TP-Link TC7620 and it has been working great. Maxes out my 105mbps connection no problem and should be some room for improvement based on the specs if Comcast upgrades my speed in the future again. The only "downside" is it won't support the phone stuff if you have triple play.

Even the modem part of the combo router/modem they rented to me was working okay, but you have to pay $10/mo to rent it and the router part of it is atrociously bad. Buying your own separate modem and router pays for itself fast and is much better than the crap they give you.

I have a Motorola Arris SB6121. Runs a little hot, but no complaints.

I think the max speeds are a little low on this one (hence why the SB6141 exists), though for my uses it's fine.

DancinJack wrote:

FWIW, DTD, that isn't necessarily about just the modem "being fast." Comcast clearly has not provisioned it properly to give you the speed you pay for. Which is awesome for you, but is also VVVVVVVVVVVVYMMV.

Actually, here's how it works: Comcast guarantees x mbps for a given tier over their equipment (ie: their modems) and network, which typically operate over 8 QAM channels downstream and 4 QAM channels upstream. They are DOCSIS 3.0 compliant and can supply additional QAMs only accessible by third-party DOCSIS modems, which are capable of providing additional bandwidth but ultimately get throttled by Comcast's own equipment upstream.

I pay for the top tier which traditionally varies from 85 mbps to 150 mbps depending on line conditions and distance from headend. In my case, they are only able to advertise it as 105 mbps. Using the additional QAMs from a 16x4 modem, they are able to provision me the full 180mbps, the maximum they are willing to provision per coax line in my area. It cannot be obtained using their traditional 8x4 equipment in my area. Additional QAMs in lesser speed areas can often still provide a performance boost because they can broadcast over additional QAMs. The speed boost part is YMMV, but it never hurts!

What DOES hurt is an overheating modem, which can throttle itself to keep temps down (in addition to costing you a few extra pennies a year). This is why I don't recommend the popular SB6141. Find another brand that will keep cool under load, or at least consider keeping it somewhere with good airflow. I was particularly drawn Netgear's lineup because of their cost, dim LEDs, and manageable heat.

I work for a company recently acquired by Comcast.

I started with the Motorola SB6121 DOCSIS 3.0 and currently have the SB6141. Now I see that Arris / Motorola has a SB6183 and even a SB6190. If your buying new and depending upon how fast of speed your will to pay for its always better to buy the fastest you can get as eventually those will become the "mainstream" speeds. The SB6190 obviously cost the most but it will pay for itself easily over its useable lifetime if it lasts 3-5 years like it should.

I just replaced my old SB 6121 modem with the 6190, and it does run massively cooler than any modem I have had before. Heck my 6121 used to get very hot sometimes, and a friend who has the 6183 gets so hot he cant even touch it. So far I am pleased with the modem, currently running 24 down 4 up and much more responsive than my 4 year old 6121.

After my ISP (Time Warner) started instituting cable modem rental charges, I bought a SB6141. It worked well for a few months, but eventually started having issues with thousands of uncorrectable errors. Switching to a Zoom 5341J (also an 8x4 modem) resolved the errors completely and gave me rock solid stable connection speeds.

I moved to a new house recently and got an introductory one year package which included 300Mbps internet, so I upgraded from the 5341J to 5370 (a 16x4 modem). I regularly get 350Mbps on speed tests with no uncorrectable errors.

Starfalcon wrote:

Heck my 6121 used to get very hot sometimes, and a friend who has the 6183 gets so hot he cant even touch it.

Mine has never gotten anywhere beyond warm to me, but I have the 100Mmps tier so I'm presently only using around a sixth of its rated capability.

Meh, probably doesn't hurt to tack a good heatsink onto the SoC anyway - consumer electronics (especially routers and modems) aren't exactly known for good cooling. Might do that to mine - heat kills electronics...

Kougar wrote:

Mine has never gotten anywhere beyond warm to me, but I have the 100Mmps tier so I'm presently only using around a sixth of its rated capability.

I really doubt any cable company is saturating the capabilities of a cable modem's QAMs. Cable modem speed ratings are like powerline adapters: they're marketed for theoretical throughput, but realistically noise and attenuation take their toll. There's just no saturating all QAMs to their 340/680/960 mbps the modems advertise, except perhaps in a lab environment. However, you will probably see a speed boost if your modem supports extra QAMs and the upstream headends support them (which they often do).

I've always stuck with and recommended Motorola/Arris modems, and they've been among the most pain-free devices I've dealt with in the land of computing. For DOCSIS 3.0, I've used the 6120, 6121, and 6141, and never an issue with heat or otherwise.

Thus far I haven't messed with any of the whiz-bang models with 16+ download channels, but I also don't know anybody willing to pay for the level of service required to take advantage of those models. Who knows though.....in a few years Google Fiber may come to town, and Comcast might suddenly jack-up all their speeds. Crazy how competition does stuff like that.

The Egg wrote:

Who knows though.....in a few years Google Fiber may come to town, and Comcast might suddenly jack-up all their speeds. Crazy how competition does stuff like that.

I know Comcast is rushing to deploy DOCSIS 3.1, which is supposed to be competitive with fiber speedwise. We'll all need new modems to pick up the extra speeds though.

Waking this thread up again.  CenturyLink has made it clear they will not upgrade the DSL in our area and our current promo rate expires in early February, so Comcast is the only option for Internet faster than 1.5mbps...which is becoming pretty much necessary now that both PCs and mobile devices are prone to downloading 50+ MB of updates whenever they wish.  Also, I'm looking at more work-from-home options in the future and need the extra bandwidth for VPN/RDP.

The service tier we get will probably only be in the 25mbps range, but since 16x4 modems are eminently affordable, I'm looking at these models as options:

TPLink TC-7620
Netgear CM500

I'm open to other suggestions, and do see Arris/Motorola/SMC options in the same price range.  Thoughts?

Stick with Arris/Motorola.

I've been running a TPLink TC-7610 for about a year without any issue.  50mbps service, the fastest here, but I usually see about 65 mbps.

I previously had a SB6141 but it died after about 6 months.

Roughly 7 years on a SB4101 and 8 on a SB6120. In my experience they just don't die, and the SB6120 will handle all of the bandwidth I care to pay for.

Another vote for the surfboard.  I had the same modem from tp-link and had nothing but trouble with it.  It behaved strangely at startup when given a new lease from Comcast which made my introduction to pfSense in a VM rather interesting.  When I wasn't making it angry by tinkering with things it behaved fine.  It needed to be power cycled at random intervals, but a lot of cheap modems do that for one reason or another.  As a replacement I got a SB6190 partly because of the reports I read about some of the older models overheating, and partly because I figured it'd be the only cable modem I'd need for the foreseeable future.

No troubles (and no heat whatsoever) from my SB6141 on Comcast for several years running. 130mbps down and 12.5 up (plan-limited obviously).

My Moto SB6120's been trouble-free for the past few years. I'm on 15/1.5.