Skip to main content

Picking a Cable Modem for Xfinity

There are a lot of cable modems on the market, and many are compatible with Xfinity service.

However, that doesn't mean that every modem is perfect.

My basic requirements are:

  • Currently certified by my ISP.  Buying a cable modem that isn't currently certified is simply unlikely to work.
  • Capable of supporting needed service speeds.  Buying a cable modem which cannot deliver the service needed is going to be an immediate bottlebeck.  Buying a cable modem which is far more capable that the service speed is likely a waste of money,
  • No built-in WiFi capability or Telephone line capability.  A personally-owned WiFi router is likely a better choice than an all-in-one unit that will need to be positioned exactly where the cable is within the house. 
  • Don't over-buy.  Cable modems do not last forever.  Manufacturers abandon support, and cable modems aren't infinitely durable due to things like lightning strikes and being powered on for years at a time.

So what are the good modems?

Assuming a very high speed plan (more than gigabit), at this point there are only two modems that meet my criteria:

Why?  Because these are the only modems that meet all of my requirements:

  • Appear on Xfinity's NextGen Speed Tier list (as of June 26th)
  • Appear on Xfinity's "Recommended" list (as of June 26th)
  • Have a 2.5 Gbit Ethernet port
  • Do not have WiFi or an "analog" Telephone port

Which one to get?  They all mostly use the same class of chipsets.  I'd get the cheapest. Shop around, as prices change.  Used modems are often good deals, as they are often just store returns that have seen little to no usage.

Slower plans

For slower plans, which is what most people should have, I recommend getting the very cheapest that meets the service plan.  For example, I bought a Arris SB6190 that can be purchased used for about $20. It has been working perfectly for years. 

Other options and ideas

  • If the plan includes a "free modem", consider using it.  Free is a good price, and the free modems are usually good.
  • For a small apartment, an all-in-one modem/wifi router might do the trick.
  • If service has been troublesome, perhaps stick with the leased modem so the provider can't pass the buck when the service isn't working well.
  • When buying, remember that your purchase may not last forever.  
    • The manufacturer may abandon the device
    • The ISP may change their technology, leaving your device obsolete
    • A new service provider may emerge with a better deal
    • You may move and end up with a new ISP
    • Your device might fail due after the warranty expires, or due to an incident 

 

 

 

Labels:

Popular posts from this blog

Fixing a SodaStream Jet, part 1: Disassembly Guide

I've had my SodaStream Jet for years, and once in a while something has gone wrong. Disassembly is the first step to repair.  Start with this article to see how to disassemble the SodaStream, and then once you have that down, scroll through my other articles to see how I repaired specfic SodaStream problems. SodaStream Jet Disassembly Guide Tools Required Flat head screwdriver Phillips head screwdriver 1. Remove the Carbonator.  Duh. 2. Remove the black panel lever The front big black tilt lever needs to be removed first. Removing this panel is tricky, but it isn't impossible. Looking up at the bottom of the black panel, there are two tabs, one on the left and one on the right. These tabs fully secure the panel in place. The trick is to use a flat-head screwdriver under the plastic to gently lever the tabs out of the way.  Note in the pictures how I approach these tabs with my screwdriver.  I usually release the left side first, and then I release ...
Read more

Sodastream Carbonator Leakage, Usage, and Weight

SodaStream 60L "Carbonator" CO2 cylinders have a specific weight when empty, plus about 410 or so grams for the CO2 they should have when they're "full".  A little while ago I went to buy a replacement Carbonator from my local hardware store. The dealer pulled a new Carbonator out of the box and sensed it was lighter than usual.  He put the "light" Carbonator in the "empty" pile and sold me a different one.  At that moment I concluded that it would be smart of me to weigh both new and empty SodaStream carbonators.  Here are the results. Weighing a SodaStream Carbonator - for both Science and Consumer Protection.       The dealer told me that sometimes the carbonators leak after they leave the SodaStream filling facility.  That means there could be an opportunity for customers like me to get ripped off! The SodaStream cylinders I buy claim to have a net product weight of 410 grams - and that means that a full Soda Stream Carbonator shou...
Read more

Mounting Devices to a Wall or Backboard

I wanted to mount an Apple TV, an HDHomerun, and a Ring doorbell transformer to a wall, but none of these devices have tabs or screw holes for wall mounting.  Happily, I found a way to easily and inexpensively wall mount equipment even if the device specifically designed with mounting in mind. There are a lot of expensive or complicated mounting options, but then there are cheaper AND better options. Specialized mounting brackets are available for many devices, but they can be stupidly expensive and then I'd have to wait for shipping.  Or I could 3D print some brackets.  My solution? I simply use zip ties and strategically placed screw-down cable tie mounts . Zip ties are very strong, and the screw mounts can be used to anchor down the zip ties while also preventing the devices from sliding out of position. This is actually far less wasteful than a specialty bracket. Special brackets use a lot of plastic. Zip ties may seem disposable, but they are actually reusable unles...
Read more

K4221C Photo Cell Adjustment

I just replaced a K4221 Photocell with a new one. The old photo cell failed in the "on" position, which is actually a great failure mode - I use the photocell to control indoor and outdoor lighting, and for safety reasons its important that it works.  So the lights being stuck "on" is a decent failure mode. But the photocell was stuck on for, um, many years.  I didn't really notice that there was a photocell, and was just accepting that the lights were on 24x365. Now with the photocell, my lights will be on roughly 16 hours a day. That saves a third off of my lighting bill.  In the scheme of things it will only save me a couple hundred bucks, but hey, rather I get it than OPEC. My photocell has a tough job.  It is to turn on necessary indoor and outdoor lighting when it starts to get dark outside.  But the challenge is that the photocell is positioned so it receives a lot of artificial light from the urban street, and it is unreasonably complex for me to...
Read more

Apple's WWDC keynote of June 2020: Big changes!

Wow, it was a big WWDC keynote. Supported Hardware: Good and Bad First, the best news: Basically all devices that can run iOS, iPadOS, and TVOS version 13 will also be able to run version 14.  That's great news, as our good hardware will be able to continue with their useful lives. But in some disappointing news, WatchOS 7 will kill off the Series 1 and Series 2 watches.  Trust me, I appreciate that old hardware is hard to keep running forever.  Hardware doesn't improve with age, especially in a highly integrated device like a watch.  Still, it will be a shame to see all those old watches heading towards the recycle bin in the next five years.  Seiko's business model looks worse than ever. Similarly, MacOS v11 kills off all the 2012 Macs.  There are a lot of them, but I guess the writing was on the wall.  So they'll get a couple more years of updates, and then people will have to do something else with them.  Happily, these old beasts can easily r...
Read more

Modernizing old house network wiring - Part 12 - PoE Power!

 I started to spend a bit more money and help things come together. PoE Switch I found a great deal and ended up buying a 10-port PoE switch. First, before we get all excited, only 8 of the 10 ports support PoE.  Secondly, it is "only" a 10/100 switch, so no gigabit for me.  I'm OK with that.  The switch was under $60, and I can always upgrade later. Laying out the Backboard I started to mount items on my backboard, including the new switch.  It took me a long time to figure out where to put the equipment: I wanted enough room to lay it all out neatly and comfortably, but I also want  efficiency.  I also want to be able to connect and disconnect items without a lot of effort.  And of course I want to be able to see status LEDs without resorting to mirrors or uncomfortable behaviors. After much trial and error, I found out that the best starting approach is to place all terminating equipment based on the building cabling.  One reality of my ba...
Read more

Other Posts

Show more