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Not getting Gigabit speeds with new XB6 modem

New Poster

Not getting Gigabit speeds with new XB6 modem

I recently installed the Gigabit connection from Comcast, and the tech replaced my earlier modem with a new XB6. However, after running multiple speed tests, I am not getting anything over 380 mbps. I understand that actual speeds will never match the advertised speeds, however I have gove through multiple posts where folks have mentioned that they are atleast getting 700 mbps. I called customer service and she tried all different options (resending the signal, changing channel settings on both 2.4 & 5 Gghz frequency), but none helped. The tech also told me during installation that speeds will never be a Gig and will be under 400 mbps.

 

Does anyone have any idea how to fix this ?

Contributor

Re: Not getting Gigabit speeds with new XB6 modem

I am currently in the same boat as you but I Am getting 700mb download on the 1gb service  make sure there are no problems in your area like on the node I cannot get the max speeds in my area I believe its because of the node I am on isn't healthy so until maintainece fixes it I am stuck I guess. I switched the XB6 modem out for a CM 1000 by netgear.

Authorized Vendor

Re: Not getting Gigabit speeds with new XB6 modem

Are you testing this on wired or wireless?  Make sure you test on wired at least once to see what you get..

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Network Engineer, IP Engineer, Docsis..; the views expressed on this post are mine and do not necessarily reflect the views of my employer..

Gamer.. Living the dream one catastrophe at a time Smiley Happy ..
New Poster

Re: Not getting Gigabit speeds with new XB6 modem

I tried it both ways..with the wired connection, the max i get is ~450 MBPS..wireless never tops ~380 MBPS..i do have the latest devices, so there is no question of compatability..
Frequent Visitor

Re: Not getting Gigabit speeds with new XB6 modem

There's a lot of factors why you may not be getting Gigabit speed- to name a few:

1) You need a high-end Network Card capable of 1Gig full-duplex throughput. Even though your computer network card may be listed at 10/100/1000, 1Gbps on the network card is only a theoretical number; you'll find most computers capping off at 500-600Mbps (so yes, your hardware can be part of the problem). I've seen a Mac computer spitting better test results (650-700Mbps) when compared to a Windows PC and I think it's because Apple focuses a little bit more on quality, hence the hefty price...but even then, it has its limits. Comcast technicians are equipped with Gigabit dongle (network) adapters and when they are connected to the modem, the speed test result -at best- should be in the mid-800s to high-900s range.

 

2) If you're still using a Cat5 cable as opposed to a Cat5e (or the recommended Cat6 and higher, Ethernet cable), well, you're doing yourself a dis-favor in getting your Gigabit speeds.

 

3) Often times, loose connectors, loose splitters, open and unused ports on a splitter, store-bought antenna cable wires, and degraded outside cables will -one way or another- affect your speed test results. So go around the house and tighten those connectors, not just the ones behind the modem. 

 

4) If you're testing wirelessly on the 5GHz network, you'll be lucky if you get past 300Mbps; I could be wrong, but I don't think there are any current phones/tablets in the US market with radio receiver capable of transferring data...at Gigabit speed. Similar to the network cards, our phones/tablets have limits and they'll vary from one manufacturer to the next. So I would avoid it if I were you, instead, do a direct wired connection test.

Contributor

Re: Not getting Gigabit speeds with new XB6 modem

as a windows 10 64bit user on a rampage v extreme motherboard my network card onboard is listed as support for the 1gb service which network card would you recommend I buy in order to try to achieve these speeds even though I am sure there is an outage in my area on my node since its showing on orange and red for alot of customers in my area.

 

Which network card would you recommend I buy ?

Regular Contributor

Re: Not getting Gigabit speeds with new XB6 modem


DNStheMenace wrote:

There's a lot of factors why you may not be getting Gigabit speed- to name a few:

1) You need a high-end Network Card capable of 1Gig full-duplex throughput. Even though your computer network card may be listed at 10/100/1000, For my wired connection I use what came with the box and get 950+ and it's just a generic PCIe Realtek adapter.

 

2) If you're still using a Cat5 cable as opposed to a Cat5e (or the recommended Cat6 and higher, Ethernet cable), well, you're doing yourself a dis-favor in getting your Gigabit speeds. Preferably for longer runs but, a typical 6ft connection doesn't really require it as long as the connectors are snug.

 

4) If you're testing wirelessly on the 5GHz network, you'll be lucky if you get past 300Mbps; I could be wrong, but I don't think there are any current phones/tablets in the US market with radio receiver capable of transferring data...at Gigabit speed. Similar to the network cards, our phones/tablets have limits and they'll vary from one manufacturer to the next. So I would avoid it if I were you, instead, do a direct wired connection test. For N speeds this might be correct but, with 5Ghz AC you can get almost wired speeds if your router/wifi card are up to snuff.  I push 650-700 on wifi after a bit of tuning of the channels and a $25 upgrade of the wifi card.  


 

Regular Contributor

Re: Not getting Gigabit speeds with new XB6 modem


animepower wrote:

as a windows 10 64bit user on a rampage v extreme motherboard my network card onboard is listed as support for the 1gb service which network card would you recommend I buy in order to try to achieve these speeds even though I am sure there is an outage in my area on my node since its showing on orange and red for alot of customers in my area.

 

Which network card would you recommend I buy ?


It shouldn't cost too much for a 1GE card these days.  I would stick with Realtek or Intel though to be on the safe side.  Anywhere from $10-$25 is more than enough to get gig line speeds.