Help! Can't figure out GB speed issue

here is what was deleted or just happens to have never posted. 

@brintonh how are you checking the speeds? with a computer? The reason i ask is, i would check your network card drivers, or network card its self, i just got a so called plug and play adapter, 2.5 gig, so it played alright, but at speeds 1/3 of what i should have got, after some research i ended up on my new adapters webpage, so on that page it said flat out you would not get the advertised speeds if you used Microsoft drivers, so i installed the correct driver, this happened, i use a xb7, so maybe install the drivers from the network adapters webpage, just a thought

@steagallcraig @jlavaseur For some reason neither of your comments are showing up.  I can see them in my emails but not on this forum. 

@brintonh "how are you checking the speeds? with a computer? The reason i ask is, i would check your network card drivers, or network card its self, i just got a so called plug and play adapter, 2.5 gig, so it played alright, but at speeds 1/3 of what i should have got, after some research i ended up on my new adapters webpage, so on that page it said flat out you would not get the advertised speeds if you used Microsoft drivers, so i installed the correct driver, this happened, i use a xb7, so maybe install the drivers from the network adapters webpage",

Response:  I have Realteck LAN built in to the Asrock motherboard.  Tried both the W10 driver but as part of my sniffing out all this problem, I installed the Realteck driver too.  Didn't make much of a difference. 

@jlavaseur I check the speeds with the W10 speedtest.net app, not the browser-based speedtests.  I consistently get 100 Mbps faster with the app.  A bit messy but here's the app vs the Xfinity Site (Chrome Browser).

Ok, just a thought here, ok so your getting the speed at the pole etc, multiple modems, so my rational leeds me to the network adapter, the fact you upgraded from a slower speed and didn't seem to have issues, personally i would try to uninstall that network adapter and reboot, i have had corrupted drivers that didn't function properly, but still worked,  just a thought

Good thought.  Uninstall through "Device Manager"?

And it'll come back when I reboot?

Yes it will, yes thru device manager

@jlavaseur Good idea.  Done.  Pulled in same Realteck driver.  No significant difference in speeds:

well here is the latest from my chat.....

From what I am seeing, the specs of your equipment on our website here: https://comca.st/3ukJD3P does only recommend the modem that you have now for speeds of up to 800 Mbps, with our new Gigabit speed being provisioned for up to 1.2 Gbps, the modem you have now can only deliver and be provisioned for up to 1 Gbps so what happens is a conflict of abilities of the modem and what we are trying to push through. We're trying to push through the right Gigabit bootfile, but that bootfile is for 1.2 Gbps which your equipment is not designed for. This is why once it is connected there is a mismatch happening and the speed is actually slowed down from its maximum ability. If you go to the website and review the devices that are recommended for the new faster Gigabit speed, you'll see there are only 5 that are listed as recommended and compatible with our infrastructure, unfortunately your current device is not listed with the new higher gigabit speed.

@steagallcraig @jlavaseur Look at the list of approved gigabit speed modems.  Check out the comments if you enter Motorola 8611 in the search function for these forums.  No better than the issues we're having!

@steagallcraig @jlavaseur Well, Step 1 complete.  Motorola MB8611 installed and provisioned.  Bottom two tests, one from last night and then again this AM, are with the Netgear CM1200.

The Netgear seems to be a little faster but not by much.  Seems when I do sequential testing (i.e., one test right after the other) it gets a little faster each time.  Still not getting close to 1 GB speed.

Step 2:  My new NIC card with 2.5G base should come tomorrow via Amazon; however, with it being Easter, might not happen so probably Monday.  The Arris SB8200 isn't back yet either.  So I'll leave the Motorola for now while awaiting the new NIC.

Step 3:  If the new NIC works better with the Motorola, I'll see if I get the same with the SB8200.  If so then the Netgear and Motorola are back to Amazon.  Here's the power levels with the Motorola:

Downstream Bonded Channels

Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected    1 Locked QAM256 32 627.0 6.9 40.9 0 0    2 Locked QAM256 1 435.0 6.0 40.5 0 0    3 Locked QAM256 2 441.0 5.8 40.2 0 0    4 Locked QAM256 3 447.0 6.1 40.3 0 0    5 Locked QAM256 4 453.0 5.9 40.3 0 0    6 Locked QAM256 5 459.0 6.0 40.3 0 0    7 Locked QAM256 6 465.0 5.9 40.4 0 0    8 Locked QAM256 7 471.0 6.1 40.3 0 0    9 Locked QAM256 8 477.0 6.1 40.3 0 0    10 Locked QAM256 9 483.0 6.3 40.3 0 0    11 Locked QAM256 10 489.0 6.6 40.4 0 0    12 Locked QAM256 11 495.0 6.6 40.4 0 0    13 Locked QAM256 12 507.0 6.7 40.4 0 0    14 Locked QAM256 13 513.0 6.7 40.5 0 0    15 Locked QAM256 14 519.0 6.6 40.7 0 0    16 Locked QAM256 15 525.0 6.8 40.7 0 0    17 Locked QAM256 16 531.0 6.4 40.8 0 0    18 Locked QAM256 17 537.0 6.5 40.8 0 0    19 Locked QAM256 18 543.0 6.2 40.7 0 0    20 Locked QAM256 19 549.0 6.3 40.6 0 0    21 Locked QAM256 20 555.0 6.6 40.8 0 0    22 Locked QAM256 21 561.0 6.8 40.8 0 0    23 Locked QAM256 22 567.0 7.2 41.0 0 0    24 Locked QAM256 23 573.0 7.1 40.8 0 0    25 Locked QAM256 24 579.0 7.1 40.8 0 0    26 Locked QAM256 25 585.0 7.0 40.7 0 0    27 Locked QAM256 26 591.0 6.8 40.9 0 0    28 Locked QAM256 27 597.0 6.5 41.0 0 0    29 Locked QAM256 28 603.0 7.0 41.2 0 0    30 Locked QAM256 29 609.0 5.9 40.9 0 0    31 Locked QAM256 31 621.0 5.9 40.9 0 0    32 Locked OFDM PLC 33 678.0 7.7 40.6 3217427 0

Upstream Bonded Channels

Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)    1 Locked SC-QAM 1 5120 35.6 43.8    2 Locked SC-QAM 2 5120 29.2 44.0    3 Locked SC-QAM 3 5120 22.8 44.3    4 Locked SC-QAM 4 5120 16.4 44.3    5 Locked SC-QAM 9 1280 39.6 43.8

@ComcastJamesH @ComcastAlyssa You guys have any further comments on what I'm seeing with the various modems?  The post immediately above is with the new Motorola MB8611.  That's now 3 different modems on your approved list for my speed tier - Arris SB8200, Motorola MB8611 and Netgear CM1200 - and also tried your Xfinity Xfi Gateway as well.

@ComcastJamesH @ComcastAlyssa 

wow. that is a 1gb plan? I am not even going down the new modem path. I will just drop my plan down to 800. Its been a year and I haven't got close to 1gb speed.