An electrical engineer and Cox broadband subscriber in our forums recently purchased the Arris SB6190, thinking it would be a notable upgrade from the Arris SB6183 and prepare him for the likely future launch of Cox gigabit broadband service in Arizona. The device, which features the Intel Puma 6 chipset, supports 32 x 8 channel bonding and is supposed to be relatively cutting edge -- at least among DOCSIS 3.0 devices.

The user, who has been charting home network performance for the better part of eight years, documented (left) just how well this new device performs. As in: it doesn't.

"The problem is extreme and, frankly, horrific," notes the user. "Arris and Intel Puma6/MaxLinear traded off speed for latency thinking no one would notice. They tossed latency out the window to get 32 bonded channels of speed. They tossed users under the bus as no user is really gonna use 1 Gbps, but they will feel the latency and latency jitter in DNS lookups."

In fact, the new modem appears to have doubled his latency before the first packet even leaves his house. The user contacted Cox, but even after ensuring the modem was running the latest firmware the problem persisted.

Curious as to why this problem exists at all, the user opened the device and discovered that Arris appears to have replaced the Broadcom chipset common to the more recent Surfboard modems, with an Intel Puma 6 chipset. There appear to have been more than a few complaints about this particular chipset floating around the internet across North America, most of them regarding the same severe latency and jitter issues xymox1 has so carefully documented. Curiously, only some reviewers appear to have even noticed the device's performance issues.

It's unclear why such a problem wasn't caught earlier by CableLabs during product certification. Whatever the cause, posts to our forum appear to indicate that Arris is aware of the problem and currently working on a firmware update. When that updated firmware will arrive in the wild isn't clear.