Bad-rated cable modems can worsen your internet surfing, online gaming, and streaming experience with higher jitter and latency. One way to spot a bad modem is by looking at its chipset. You should avoid getting it if it comes with an Intel Puma 6 or 7 chipset.
With the help of network security experts and various forum users, we’ve finally found faulty networking modems that create performance-related issues. In some cases, manufacturers have taken action on the raised issues and claim they’ve resolved them, but why take risks when there are plenty of good modems with better chipsets and technology?
You can jump to the list of bad-performing modems below, but if you’re looking for the best modem recommendations, I’ve ranked and reviewed the top-rated options for different internet providers & their different plans in the US. Here they’re:
List of Bad Modems To Avoid in 2023
Here is the complete list of underpowered modems that one must refrain from buying. While the primary focus was on the Intel Puma 6 chipset modems, I also included the ones with Intel Puma 7 processor. Though the experience with them is not as bad as Puma 6.
- ARRIS CM3200
- ARRIS DG1660
- ARRIS DG1670
- ARRIS DG2460
- ARRIS DG2470
- ARRIS DG3260
- ARRIS DG3270
- ARRIS DG3450
- ARRIS SBG10
- ARRIS SB6190
- ARRIS SBG6950AC2
- ARRIS SBG7400AC2
- ARRIS SBG7580AC
- ARRIS SBG7600AC2
- ARRIS SBG8300
- ARRIS SBV2402
- ARRIS SBV3202
- ARRIS SVG2482AC
- ARRIS T25
- ARRIS TG1652
- ARRIS TG1662
- ARRIS TG1672
- ARRIS TG1682
- ARRIS TG2472
- ARRIS TG3452
- ARRIS TM1602
- ARRIS TM3402
- ASUS CM-32
- Hitron CDA3
- Hitron CDA3-35
- Hitron CGN3
- Hitron CGNM-2250
- Hitron (CGNM) CGNM-2252
- Hitron CGNVM-2559
- Hitron CGNM-3550
- Hitron CGNM-3552
- Hitron CGNVM-3580
- Hitron CGNVM-3582
- Hitron CGNVM-3589
- Hitron CODA-45
- Hitron CODA-4502
- Hitron CODA-4580
- Hitron CODA-4582
- Hitron CODA-4589
- Hitron CODA-46
- Hitron CODA-4602
- Hitron CODA-4680
- Hitron CODA-4682
- Hitron CODA-4689
- Hitron CODA-47
- Hitron CODA-4702
- Hitron CODA-4780
- Hitron CODA-4782
- Hitron CODA-4789
- Linksys CG6350
- Linksys CG7500
- Linksys CM3016
- Linksys CM3024
- NETGEAR C6300
- NETGEAR C6300v2
- NETGEAR C6300BD
- NETGEAR CBR40
- NETGEAR CM700
- Cisco DPC3848V
- Cisco DPC3941B / DPC3941T (commonly, Comcast Xfinity XB3)
- Cisco DPC3939
- TP-Link CR7000
- Compal CH7465-LG / Arris TG2492LG (commonly, Virgin Media Hub 3)
- Samsung Home Media Server
- Super Hub 3 (Arris TG2492LG) (commonly, Virgin Media)
- Telstra Gateway Max (Netgear AC1900 / C6300) (Australia)
How To Identify Cable Modems To Avoid?
Troubleshooting the modem can help you intercept the effectiveness of the same. There are quite a few techniques to check whether the device is defective.
- Performing a speed test is a good way to check for latency, followed by the jitter test. Perform it using: Speedtest by Ookla / Cloudflare Speed test
- A ping test can be used for concerns related to packet dropping.
- Intel Puma 6 chipsets: It is advisable to avoid any modem that has the Intel Puma 6 chipset in it.
However, few brands do not feature logos on the package. For that, you can always refer to the featured list at the bottom for enlisting the modems to avoid.Kurt TWAIN, APPROVEDMODEMS.ORG
Intel Puma 6/7 Chipset
Modems featuring Puma 6 and 7 chipsets are known to experience speed, jitter, and latency-related issues. In simpler terms, they take a lot of time when it comes to processing network packets.
Initially, it was the gamers who identified this issue upon encountering lags. Eventually, what was presumed to be a minor hardware issue, turned into a big-discovering lawsuit!
The Puma 6 chipsets had bugs responsible for throttling the speed of operations. Moreover, the bugs even opened up avenues for pranks. It was possible for the attackers to determine the low-bandwidth streams and eventually force the modem offline.
The Puma 6 Bug also makes way for connection lags courtesy of smaller payloads. Not just that, but these bugs were also discovered in Puma 5 and Puma 7 chipsets.
The mentioned bugs made the Puma 6 modems prone to several performance-hindering vulnerabilities. The major one under consideration was the performance loss. The worst-case scenario involved packet exhaustion right at the inception stage.
In addition to that, the vulnerabilities also made way for the spike in network latency. In most cases, increased latency made way for sub-par gaming and interactive performances. Moreover, the attackers could even blow off the adjoining hardware in a few cases.
From a more technical standpoint, the associated vulnerabilities ensured that processing network packets was slow. The CPU side-tracked the essential tasks and allow the pranksters to take up all the resources belonging to the SoC. While the optimal latency range is 20ms-40ms, these modems even experienced something in the ballpark of 200ms.
Rogue tasks ate up the speeds and resources allocated for basic networking activities. Moreover, an almost 6 percent drop in either IPV4 or even IPV6 packets was encountered. The x86 Processor couldn’t handle high-maintenance tasks like gaming and hogged up the processor, spoiling gaming and other online activities.
Vulnerabilities included driving the modem offline via low-bandwidth streams. In certain cases, even one percent of the requisite bandwidth resulted in a modem crash.
However, to exploit these vulnerabilities, the attacker must know the IP of the concerned user. That said, other issues involving jitters and latency persisted even without attackers running foul.
The more demanding activities and even basic online interactions get thwarted due to the existing vulnerabilities.
Defective Puma 6 chipsets in select modems eventually led to a consumer class-action lawsuit. Schubert Jonckheer & Kolbe LLP is the law firm investigating the matter and fighting the class action on behalf of ill-fated customers.
Initially, the lawsuit concerned Arris International as their modems initially showed signs of defects. With customers experiencing a spike in latency and degraded connections, the lawsuit was quite an obvious choice.
Both Arris and Puma accepted the issues and defects but did nothing in regard to solving the issue. Therefore, as part of the remedial plan, authorities instructed the company to refund the full modem value, in case the user ends up getting a defective piece.
The concerned law firm eventually moved on to other manufacturers selling modems containing the Puma 6 SoCs. The companies under the scanner were Linksys, Hitron, Cisco, and Netgear.
Based on the vulnerabilities and bugs listed above in the discussion, users who have purchased a defective modem can file issues separately with the law firm. This way, they become eligible for updates and even compensation based on the culmination of the class-action lawsuit.
The common theme of the class action is based on the violation of consumer protection standards in the US.
Why Should You Avoid Affected Modems?
There are quite a few reasons why you must refrain from purchasing bad modems. Here are some of the threats that come along with the faulty Puma 6 modems.
- DDoS Threat: Modems sheltering the Puma chipsets, including Puma 5, Puma 6, and even Puma 7, are prone to DDoS attacks. The attacker can easily tap into the network if your IP address is known. Eventually, you might start experiencing timeouts and resource depletion. Do you want it?
- Increased Latency: The modems with Puma chipsets increase network latency and negatively impact online activities. Increased latency means gaming and other web-based activities take longer than expected as the modem keeps dropping the network packets.
- Modems featuring Puma chipsets can cause an almost 6 percent drop in network packets, leading to the highest possible network latency of 200ms.
- Higher Jitters: Jitter is determined by the spread of latency across timeframes. Puma 6 chipsets ensure the networking latency varies from 2 seconds to even 0.001 seconds or even more.
Therefore, besides slowing down the speeds, the interactive experience over the internet is frustrating and completely random. Jitter is one aspect that affects game-playing the most.
Has The Puma 6 Chipset Been Fixed Now?
Even after several firmware updates, the Puma 6 chipsets haven’t been fixed yet, as of 2023. It’s a hardware limitation that this Intel chip can’t handle higher speeds and lower latency. However, in newer modems, most manufacturers go with Broadcom chips.
To start with, ARRIS started the initiative by resorting to the Broadcom chipsets instead the Intel-powered ones in select devices.
Another strategy certain modem manufacturers use is setting up compatible firmware on the gadgets. This approach includes blocking the slow and jittery sequence of packets that hinder the performances. However, companies are rolling out firmware updates at a very slow pace.
A faulty cable modem can hinder your online experience, making you prone to threats and vulnerabilities. Not just that, there are several safety concerns to account for.
While only modems with Puma 6 chipsets showcased issues, there are updates even the certain Puma 7-powered devices crashed courtesy of the existing Intel-specific hardware issues or an entirely different bug.
Most importantly, Intel has decided to exit the business while focusing all its efforts on improving network infrastructure.
Therefore, keeping a close eye on this list of defective modems and staying away from the featured models while making the purchase is necessary.
is the Puma 6 chipset and IpV6 the same thing. I want to buy a new modem and I want to avoid getting one with Puma 6 chipset. As a computer novice, the only way I can identify it is to reasd the box or modem description on the internet. HELP!!!!
IPv6 is a networking protocol unrelated to any specific hardware. IPv6 is a replacement for the older IPv4 protocol (IPv4 being a 32-bit address and IPv6 being 128-bit). Puma 6 is a particular chip or set of chips in a modem, which could run a variety of protocols (IPv4, IPv6, etc).
Janice Ellison says
Is there a good modem for SuddenLink?
Tiffany bolton says
I used the Netgear CM600 with Suddenlink and it lasted for about two years before having unusual issues with download speed. It has the Broadcom chipset. I have just replaced it with Motorola MB7621, and my download speeds have returned and it has a two year warranty and the Broadcom chip 24×8.
Myra Rochelle says
I have Optimum Triple play with TV, landline phone, internet. I don’t watch TV at home so I don’t know if it works well or not. However I rely on the internet service (300) speed and the phone. Since november 2014 my connection is with the rental Optimum modem Arris TM822. The internet and phone are working fine. I have an old HP laptop still running Windows 7 Home.
Unsolicited, Optimum sent me another modem which is an Arris TM1602. This TM1602 is on your BAD list. What should I do. Should I just stay with the TM822 modem which is working fine for my purposes? I am afraid to change. I spoke with two Optimum technicians. Both told me it is fine for me to stay with my current modem. They think changing to the TM1602 is OK, too. I will have to call and tell them about your BAD modem list.
Kurt Twain says
Myra, I’m sorry for the late response.
The Arris TM1602 is a bad modem because of the chipset present in it. There are chances that your internet experience can suffer because of it. However, it’s one of those devices that come with phone jack support and is compatible with Optimum.
In case you need the landline phone to work then I think that’s your only option. However, if you don’t use their voice calls facility, then check out my list of best-rated Optimum compatible modems: https://approvedmodems.org/optimum/
You say the Arris TM1602 is bad but yet it is on your “list of best-rated Optimum compatible modems: https://approvedmodems.org/optimum/“
Why is the Arris T25 blacklisted? It has a Puma 7 chipset, not the problematic Puma 6. (Really asking.) Thanks!
Andy Castle says
Puma 5,6,and 7 are all problematic and in the same boat! All 3 were manufactured in short, with the tools to help your provider throttle its customers. The development of these tools came at a cost of major vulnerabilities and devastating performance defects. Honestly it’s kinda karma as far as I am concerned for helping providers to throttle customers without them being aware or notified!
Intel released security fixes to address a lot of this issues. You need to work with your MSO/Cable Provider and they in turn should work with Intel to get the base code updated patches.
Michael Upset says
BASTARDS!!! Xfinity knew about this for three years! My Internet experience has been crap for more than a year now of leasing an Xfinity ARRIS TG1682G modem. Not only is connection crap, but the modem restarts at least once every day!!!
And Xfinity did not recall this modem by now!!! I am going to buy Motorola MB8611. I have to turn in my leased modem. I am sure that this modem will be just passed on to another unsuspecting customer!!! Sue Xfinity, recall these crap boxes!!!
I had a puma 7 modem router combo and have had no issues really… So I think most of the issues have been fixed on newer modems..
I have read that the ARris sbg8300 has “ARM and ATOM application processor”. This is the only site I have found saying it has the puma chipset. Did they (arris) change chipsets?
I was just in c p ntact with Arris. They emphatically refused to identify the chipset in the sbg8300. Does that answer your question?
It’s a D3.1 modem – so not even Puma 6. Does that answer the question?
This was a 2016, and the early firmware updates were promising. Is this still an issue? (2022)
No, it’s not anymore. It has been fixed years ago but for some reason this ‘news’ keeps popping up. The claim about the newer chipset is also false.
I have been fighting with my ASUS CM-32 for two years now. Randomly going offline. All the while the modem was showing it was connected to the internet. Hellish.
I’ll be checking your site from now on AND passing it on to my friends. Got a good deal on an MB7420 came home and searched for reviews. BAM! Here you are. I appreciate your methods and your comments. Thank you
I have recieved a ARRIS TM 1602a modem as a replacement for the one I have now, via Spectrum to “upgrade my equipment” After reading all the problems with this model and how I can fix them !!! Im not keeping it. What a farce.