Xfinity & Arris S33 and W121 Kit - slow speed issue

What wired speeds do you get? 

Hardwire in a pc/laptop to the router and test what speeds you get directly using the speedtest site xfinity has. 

IF that only gets 400, then hardwire the pc/laptop directly to the modem (you’ll have to disconnect the router and reboot the modem or you won’t get a connection). Test that speeds directly. 

The goal is to figure out where the bottleneck/slow down is. Its not abnormal for wireless speeds to only hit 400mbps as there’s a ton of factors that influence wifi speed. But wired speeds should hit that 1gig speeds you pay for. 

Hi,

thanks for the reply. Appreciate it. 

I hardwired my Laptop directly to the S33 Modem 2.5GE yellow port and run about 5 tests in xfinity speed test website : 

Download : 279.3 MBps
6.1 Mbps upload

Download 295.2
36.7 Mbps upload

Download 325.5
37.1 Mbps upload

Download 341.3
38.3 Mbps upload

Download 344.7 Mbps
34.1 Mbps upload

Please let me know if you need more details 

Thanks 

Hi,

This evening i called Comcast and complained on the poor speed. 

the rep told they are adjusting signals and it will be better in 2 hours, i dont believe that they could fix this remotely like they are suggesting (?) 

Attached is the connections status page post the Comcast signal fixing 

Current System Time:Wed Feb 5 21:49:46 2025

did it help the speeds? Those signals look pretty solid (upstream is a little low but if you’re close to a hub, might be fine)

Hi,

Yes the speeds are better now, will continue to monitor this further. 

thank you for your help in responding to my request. Appreciate it much. 

glad it improved!