TR Forums

Hi there,

Buying a cable modem soon as moving to Comcast (leaving U-Verse coverage and don't want to deal with DSL).

Should I get an SB6120 or SB6121? The complaints I see about the 6121 are that it's warmer and more expensive. That said, is there any benefit to the extra cost associated with that modem compared to the 6120? Seems like I should just go with the 6120 unless there's an overwhelming reason for the -21.

Also... for routers. I know an n router is supposed to be faster, but that's about it. I know and have experience with the old Linksys WRT54GL... and I was planning on just grabbing that, unless of course there's a significant reason to get an n level wireless router. Thoughts on that?

Thanks!

I have the SB6120 and have been very happy with it. Looks like the 6121 is a smaller version than the 20...although the 20 is not that big to start out. As for heat issues, the mesh venting on the 20 is good and I have yet to see it even warm unlike my previous 5120, that always ran very hot, and is prob why it eventually failed.

Chalk up another happy SB6120 owner. I've had it for a year now, it replaced my aging SB4200 when I realized Comcast was not only still charging me for it, but decided to up the monthly fee.

Performance has been good. It was faster even pre-DOCSIS 3.0, but after the switchover last December here, it's even better.

I just installed an SB6121 for my parents (goodbye, DSL!). It works well.

I love my SB6120 as it's got enough oomph to push the upstream through the too-often-spliced cable lines here in VT. It'll push upstream of 58-60 dBmV and stay connected where the old SB4200 crapped out at 52 dBmV or so.

Interesting how many people still have the trusty old SB4200, I got mine back in early 2001 or so, used it for around 5 years or so before I replaced it, and then gave it to my mom to use so comcast would not charge her for a modem rental. I just replaced the 4200 to a 6120 due to the 4200 dying from a lightning strike, but it lasted 10 years of service...impressive by tech standards.

Starfalcon wrote:

Interesting how many people still have the trusty old SB4200, I got mine back in early 2001 or so, used it for around 5 years or so before I replaced it, and then gave it to my mom to use so comcast would not charge her for a modem rental. I just replaced the 4200 to a 6120 due to the 4200 dying from a lightning strike, but it lasted 10 years of service...impressive by tech standards.

The 4xxx series Surfboards, IMO, were just built better than the models that came after up until the 6-series. Sure, they were only DOCSIS 1.1, but they were consistent and didn't die easy.

Now though, it's worth going to DOCSIS 3 if your area supports it. Even at the lowest speed tiers, I've found the multi-channel setup to be faster and more consistent under load.

The one big thing I miss about the SB4200 was its internal power supply, so it didn't use a wall-wart AC adapter. I wish the SB6120 used at least a small power brick instead, easier to plug in on a UPS or surge strip.

i went with the SB6121 when i bought my own modem. I got it on sale so it was only $7 more than the 6120 at the time. it works fine for me. my cable internet provider doesnt have bonded pairs for upstream so the max upload speed they have is 2 MB but downstream does which is 16 MB over 3 channels.