Bumped up to 900 MBS plan, getting ~450

What does Xfinity support have to say?  I have 1gig and my download speed, just checked, is 983mb hardwired.  They are generally very good at troubleshooting.  Also, is your laptop capable of 900Mb?  I had some old switches I had to upgrade.  They were not capable of gigabit.  If you look at the speed tiers they sell, your speed should never be lower than the next tier down.

BTW, my cable modem is the Xfinity one

Hello,

Thanks for the quick response. I have opened a ticket with support and have not heard back yet.... 

I have multiple machines (laptops/desktops) with gigabit ethernet capability seeing the about the same speed, the switch is also a gigabit capable.

Cheers

Anything that doesn't completely [Edited: "Language"] (by 2022 standards) should be able to deal with 1Gbps over a wired connection.  950 or so on a speed test.  Apple doesn't make [Edited: "Language"] so an Apple product would have to be really old.  On the PC side a 10yo dual core i3 Windows laptop should be able to handle 1Gbps no problem, but you can get cheap trash netbooks that might have an issue.

At any rate the best way to test Comcast's performance is with a wired/cabled connection, so keep doing what you're doing.  You should check the signal stats and error log on your Arris S33 modem and go ahead and post them on here.  Just be sure to redact any MAC addresses (CM-MAC, etc.) and routable IP addresses from the error log.  The forum considers these private personal information and won't allow you to post them.  Also use cut and paste on a computer if you can rather than taking screen shots and posting images.  The forum does quite well with pasted tables and they come out looking a lot better than screenshots.

Hello, @user_07d598, thanks for reaching out to our forums for help with your slow speeds. I can imagine the reaction when you upgraded your speed tier and modem, only to be bummed out by a slow speed. I have your back and will work with you until we get your speeds in line with where they should be. We only guarantee our speeds over a hardwired connection, so we definitely have some work to do. I see that you sent us a direct message, but I'd like to continue working together publicly as long as possible. This way we can help as many people as possible. If we get to a point where account access is needed, we can go to a DM. Is your PC the only device getting slower speeds? Do you have another ethernet cable or a cat6 or above ethernet to test? As a friendly reminder for next time, please wait to send a DM until being requested by an official employee. Unsolicited DM's are a violation of our Guidelines. 

Hello, thanks for the response. 

Apologies for reaching out via DM, I was following the instructions that were provided to another user and I must admit I didn't think to look at the guidelines.

To answer your questions, 

- I have tried multiple cables with the same result (mostly Cat5e and a couple of Cat6)

- I have several modern PCs with hard wired ethernet connections getting the same result (the most recent machine is an i7-12700 gaming PC)

I am using a gigabit switch. Seems like we should remove this variable. Can I change the MAC Address associated with my connection directly, or do I need to go through the modem activation process again?

Any other actions that I should be taking?

- 

Status from Arris S33...