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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 2024

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.

  1. ARRIS CM3200
  2. ARRIS DG1660
  3. ARRIS DG1670
  4. ARRIS DG2460
  5. ARRIS DG2470
  6. ARRIS DG3260
  7. ARRIS DG3270
  8. ARRIS DG3450
  9. ARRIS SBG10
  10. ARRIS SB6190
  11. ARRIS SBG6950AC2
  12. ARRIS SBG7400AC2
  13. ARRIS SBG7580AC
  14. ARRIS SBG7600AC2
  15. ARRIS SBG8300
  16. ARRIS SBV2402
  17. ARRIS SBV3202
  18. ARRIS SVG2482AC
  19. ARRIS T25
  20. ARRIS TG1652
  21. ARRIS TG1662
  22. ARRIS TG1672
  23. ARRIS TG1682
  24. ARRIS TG2472
  25. ARRIS TG3452
  26. ARRIS TM1602
  27. ARRIS TM3402
  28. ASUS CM-32
  29. Hitron CDA3
  30. Hitron CDA3-35
  31. Hitron CGN3
  32. Hitron CGNM-2250
  33. Hitron (CGNM) CGNM-2252
  34. Hitron CGNVM-2559
  35. Hitron CGNM-3550
  36. Hitron CGNM-3552
  37. Hitron CGNVM-3580
  38. Hitron CGNVM-3582
  39. Hitron CGNVM-3589
  40. Hitron CODA-45
  41. Hitron CODA-4502
  42. Hitron CODA-4580
  43. Hitron CODA-4582
  44. Hitron CODA-4589
  45. Hitron CODA-46
  46. Hitron CODA-4602
  47. Hitron CODA-4680
  48. Hitron CODA-4682
  49. Hitron CODA-4689
  50. Hitron CODA-47
  51. Hitron CODA-4702
  52. Hitron CODA-4780
  53. Hitron CODA-4782
  54. Hitron CODA-4789
  55. Linksys CG6350
  56. Linksys CG7500
  57. Linksys CM3016
  58. Linksys CM3024
  59. NETGEAR C6300
  60. NETGEAR C6300v2
  61. NETGEAR C6300BD
  63. NETGEAR CM700
  64. Cisco DPC3848V
  65. Cisco DPC3941B / DPC3941T  (commonly, Comcast Xfinity XB3)
  66. Cisco DPC3939
  67. TP-Link CR7000
  68. Compal CH7465-LG / Arris TG2492LG (commonly, Virgin Media Hub 3)
  69. Samsung Home Media Server
  70. Super Hub 3 (Arris TG2492LG)  (commonly, Virgin Media)
  71. 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.


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 Bugs

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.

The Lawsuit

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.

  1. 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?
  2. 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. 
  3. Modems featuring Puma chipsets can cause an almost 6 percent drop in network packets, leading to the highest possible network latency of 200ms. 
  4. 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. 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.