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ARRIS SBG-7580-AC Owner told 1 gig internet no longer supported (500mbps max)

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ARRIS SBG-7580-AC Owner told 1 gig internet no longer supported (500mbps max)

When I purchased my ARRIS SBG-7580-AC 2 years ago it was listed as compatible with Xfinity's 1gig speeds that had just arrived in Houston. 

 

After a conversation with support, I'm now told that same modem no longer qualifies for 1gig internet and can only be provisioned for 500mbps internet. Strange considering the modem supports 32x8 bonding. So, for anyone Googling about this modem or considering purchasing product that currently lists as being supported by Comcast Xfinity,  beware that your product may become incompatible with speeds you pay for and it's up to you as a consumer to test your downstream and make corrections, because Comcast won't tell you.

Expert

Re: ARRIS SBG-7580-AC Owner told 1 gig internet no longer supported (500mbps max)

It's not the number of downstream channels that matters for gig speed as Comcast will only deliver gig speed via a DOCSIS 3.1 capable modem. The 7580 is only DOCSIS 3.0 capable.



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Re: ARRIS SBG-7580-AC Owner told 1 gig internet no longer supported (500mbps max)

What changed between DOCSIS 3.0 and 3.1? I used to get 900mbps+ speeds on my Gig tier plan.

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Re: ARRIS SBG-7580-AC Owner told 1 gig internet no longer supported (500mbps max)


@Abom wrote:

What changed between DOCSIS 3.0 and 3.1? I used to get 900mbps+ speeds on my Gig tier plan.


What make and model modem were you using to get that speed?  I had to get a DOCSIS 3.1 modem in order to support gigabit.


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Expert

Re: ARRIS SBG-7580-AC Owner told 1 gig internet no longer supported (500mbps max)


@Abom wrote:

What changed between DOCSIS 3.0 and 3.1? I used to get 900mbps+ speeds on my Gig tier plan.


https://www.google.com/search?q=docsis+3.0+vs+3.1&rlz=1C1SQJL_enUS782US782&oq=SDOCSIS+3.0&aqs=chrome...



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Re: ARRIS SBG-7580-AC Owner told 1 gig internet no longer supported (500mbps max)

I was using the SBG-7580-AC for at least a year with gigabit speeds. they changed the boot file on the modem and now only provision the SBG-7580-AC for the next tier down (400Mbps). When I purchased the modem it was listed as supported, the same way the CM1000s are now, under Comcast's gigabit plan. It appears that since they've switched ti DOCSIS 3.1 as mandatory for gigabit speeds, they will no longer provision my previously supported modem for gigabit internet.

 

I've Googled Docsis 3.0 v 3.1. I thought you might have better insight other than im being forced into planned obsolescence.

Expert

Re: ARRIS SBG-7580-AC Owner told 1 gig internet no longer supported (500mbps max)

Uh. "Insight" Really ???Don't know what you were *expecting*. BTW, I'm not a CC employee.... Don't know what you saw but they never delivered gigabit speed via a DOCSIS 3.O modem...


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Re: ARRIS SBG-7580-AC Owner told 1 gig internet no longer supported (500mbps max)


@Abom wrote:

I was using the SBG-7580-AC for at least a year with gigabit speeds. they changed the boot file on the modem and now only provision the SBG-7580-AC for the next tier down (400Mbps). When I purchased the modem it was listed as supported, the same way the CM1000s are now, under Comcast's gigabit plan. It appears that since they've switched ti DOCSIS 3.1 as mandatory for gigabit speeds, they will no longer provision my previously supported modem for gigabit internet.

 

I've Googled Docsis 3.0 v 3.1. I thought you might have better insight other than im being forced into planned obsolescence.


 

There's no "planned obsolescence" here. Comcast has never maintained that you could use a DOCSIS 3.0 modem for gigabit, ever.  I don't know who you talked to or where you got your info, but when I signed up for Gigabit back in August 2016, I was told in no uncertain terms that I either had to use the leased Comcast XB6 gateway, or purchase a DOCSIS 3.1 modem.  I had to use the XB6 for a time as I was unable to purchase a DOCSIS 3.1 modem that included telephony function. (I have the Netgear CM1150V now). 

 

The SBG7580-AC is listed under manufacturer's specs as being capable of 1.4 Gb/sec, sure, but that's not under real world conditions. If Comcast were to allow every DOCSIS 3.0 modem to bond 32 downstream channels at gigabit speed, it would soak up bandwidth and restrict access for everyone. Possibly, your local node didn't have as many subscribers at first, so you could use soak up bandwidth on your modem, but that would've been a major fluke.  Someone probably saw what was happening and corrected it. 

 

 


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Re: ARRIS SBG-7580-AC Owner told 1 gig internet no longer supported (500mbps max)

I got my info from the device info page in early 2017. It's why I purchased the model I did. At that time it was listed as supported for gigabit speeds in the Houston market. It's still listed as supporting up to 921Mbps on the device info page on Comcast's website (https://mydeviceinfo.xfinity.com/device/arris-sbg7580-ac-554) but Comcast no longer provisions it for the 1 gig tier. One of the tech supports I spoke to had a similar incident with the same complaint and modem earlier in the week.

 

Regardless, Comcast is no longer competitive for internet in my market. AT&T offers gigabit fiber, no fee on the modem, and unlimited data for $60/month pretax.