Review on 🔌 NETGEAR Cable Modem CM400: Xfinity, Spectrum, Cox Compatible, Up to 100 Mbps, DOCSIS3.0, Black by Brian Cooper

START OVERVIEW: This modem was purchased to replace another NETGEAR modem that was one month out of warranty. This one only lasted a month so I'm replacing it with another of the same kind. I'll try again - will update this review if the new one lasts longer. UPDATED REVIEW: Alright, the new device started having the same issues after just a few weeks. I decided to investigate this further and here is what I found. This modem uses an embedded chip called "Puma 6". This chipset has a known issue that causes "buffer bloat" which can result in high latency. If you do a proper test, you'll likely see it show up as network jitter when your modem is under load. The problem can come and go, making it hard to spot, but there are good tests you can run to see if it is. If you do a little research you can find a summary of this information on other websites as well. This problem does not affect everyone. It depends on how demanding your internet is and what apps you use. For example, you'll hardly notice it if you're just surfing the web and reading email. As you play, chances are you'll notice this. Also, there are some reports that this issue is regional as firmware is deployed in different regions, but I couldn't find any hard data on this, so it seems speculative at this point. A security bulletin has also been published. NETGEAR (in 2017) and stated that it was one of several modems that were subject to DoS attacks. To be fair, most people wouldn't fall victim to such an attack, but that's another thing to keep in mind. I haven't been able to find any information on whether or not they've fixed this issue yet. So if you use the internet like my grandma, you don't mind daily modem resets and internet speeds 20% of what the modem advertises (or somehow being one of the lucky few who don't have problems with that modem). This will probably work for you. If this doesn't apply to you, find out which modems come with the Puma 6 chipset and DO NOT BUY THEM.