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SBG 6580 slow connection- COMCAST cap speeds?

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Re: SBG 6580 slow connection- COMCAST cap speeds?

When I went to look it up it doesn't even show up as an option @


Might be time to upgrade....  Also, there's a promo page for some discounts for particular devices.


Every region is different in what they support.... what I see may be different from what you see along with what speed tiers they'll provide depending on the modem.  I would recommend going with a split setup with a modem and a router instead of combining them into a single device.  You have more control over them when it comes to setting them up but also more control when it comes to upgrading them in the future.  At a minimum I would opt for a 16x4 channel modem but, 32x8 would be better as it will last longer as technology advances and CC hands out more bandwidth.  Ideally a D3.1 modem would last the longest as far as not needing to get a new modem for even longer.  (CM1000 / MB8600 / SB8200) These 3 models are the D3.1 modems on the market currently and they're all pretty much the same when it comes to the guts inside.  The advantages are going to depend on the amount of GigE ports on the back when the option for multi-gigE gets released in the future.  


Re: SBG 6580 slow connection- COMCAST cap speeds?

According to the Comcast device approved list that gateway cannot handle those 250Mbps speeds so no config file for it most likely.
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SBG 6580 slow connection- COMCAST cap speeds?

Capture.JPGAre there any knowledgeable Comcast employees on this board?

Online chat support told me that this modem only supports 150MB download speeds. I am paying for 250 down.

 The firmware Version is SBG6580-


Since ARRIS Specs show 343 Download, I assume Comcast provides a config file with 150MB capped.

After I first had the modem added and provisioned, it was getting 15MB/2MB. after they reset it, I was getting about 97MB/4MB hardwired ethernet connection. Wireless on this modem, just 6ft from the device, I may get between15-40MB down and just 2-4 up. Levels look fine. Is Comcast capping these speeds? I don't understand why Comcast would say that it's a supported device, and not allow the device to operate at full capacity.