ARRIS SURFboard S33 DOCSIS 3.1 Multi‑Gig Cable Modem | 2.5Gbps + 1Gbps Ethernet Ports | Works with Xfinity, Cox, Spectrum | For Cable Internet Plans up to 2.5Gbps | Modem Only, Router Required

I should start out by stating that I am an IT professional, and have been in the industry for 24 years. I have a family of 6, all of whom are doing school remotely in this COVID world, and I've worked from home for the better part of the last 8 years, so home Internet is my livelihood. I also have one gamer in the family who tests bandwidth and connectivity to its limits for me. We moved (in town) November of 2020, so I have been on a Netgear C7100V for the past 5 months. Which, granted was its own Wifi router (2-in-1) and had a smaller price point, AND was an older model than the Arris S33. For the last 45 or so days, while on the old Netgear, my Xfinity connection had been dropping periodically. Turns out the Netgear C7100V was recently removed from the compatibility list. I figured I better buy a new modem that was on the list before I call Comcast and complain because the first thing they're going to say to me is go buy another modem before they'll support my problem. Buddy of mine in IT had the Arris S33 Surfboard, and raved about it, so I thought I'd give it a try. And because my old Netgear was a modem/router combo, I had to purchase routers too, so for context, I should disclose that I also upgraded to an Eero 6 pro 3-pack tri-band mesh wifi6 router system too. BUT, I can say unequivocally, that I never got anywhere close to the 1Gbps speeds I was paying for with the Netgear C7100V. 600mbps, tops, which is a bandwidth limitation of that device that I lived with and dealt with because no one ever got 600mbps TO the modem over wifi anyway, so the bottleneck was before the Internet egress before anyway, and still is, and probably always will be with wifi, but I digress. But with this Arris S33 Surfboard modem, I get a consistent, all day, everyday, 900+mbps of my 1gbps service. And, so far, no drops in service either since installing the Arris (fingers crossed it's only been 3 days). But even if I do, this review is still relevant because if I continue to experience drops even after the new modem and router, pretty sure it's the service provider at that point anyway. It's smaller, easy to use, quick simple setup, and if you have the Xfinity app on your phone there's no need to even call Comcast. You don't need to be an IT pro either. It took, like 20 minutes to setup, using the included quick setup guide, and it's been "set it and forget it" ever since (again, so far). I'll come back and revise this review if that changes, but I have no complaints.

This is my second time buying the ARRIS S33 DOCSIS 3.1 multi-gigabit cable modem—because lightning apparently decided my internet setup was too good and struck down my first one like Zeus himself was having a bad day. RIP, my beloved modem, you lasted just long enough to show me what true speed feels like before being vaporized in a flash. But honestly? I’m not mad. The ARRIS S33 is a beast. It supports DOCSIS 3.1, meaning it’s ready for the next-generation high-speed cable internet—like, up to 2 Gbps downstream and 1 Gbps upstream (if your ISP and plan are playing along). It’s also backwards compatible with DOCSIS 3.0, so if your ISP hasn’t fully upgraded yet, no worries. Installation is impressively painless. Plug and play, with support for IPv4 and IPv6, and it handles channel bonding like a champ—aggregating multiple channels to maximize throughput and minimize lag. I’ve thrown all kinds of traffic at it: 4K Netflix, intense online gaming sessions, video calls where my face looks mostly presentable, and it doesn’t even break a sweat. The only caveat: lightning doesn’t play nice with electronics. So if you live somewhere prone to storms like me, consider a surge protector or UPS, unless you want to keep buying backup modems like this is a weird hobby. Bottom line: the ARRIS S33 is fast, reliable, and future-proof enough to handle whatever Comcast Xfinity throws at it. Just pray to the weather gods to keep your modem alive.

This Arris Surfboard S33 modem runs extremely, extremely HOT 🔥🔥🔥! The coverage is sporadic and glitches out to my router all the time. My Asus router works fine. Arris has a problem with this modem overheating. It does not vent well. It desperately needs revisioning. Start over, do it right! Don't cheap out on your customer to save a few pennies. They keep your business in business. Heat sinks or an internal fan or both need to be implemented and utilized. A better case to allow for improved air flow should also be considered. Arris must know about this design flaw and be okay with it. The modem will just eventually burn itself out. Electronics will eventually break down by continuous heat and overheating. This is just hot to the touch, and it is unacceptable. I am very unhappy with this company and their modem. It could even possibly be a fire hazard. I give it a negative rating and negative stars. I do not endorse this hunk of junk by Arris. Choose another company. There are so many other better options available. Learn from my mistake. This is a terrible excuse for what a modem should be. Update 1-10-24 This is the most dismal, disappointing modem that I have ever owned constantly dropping the connection. This morning, I had no connection to the internet. I had to unplug everything. I thought maybe if I rebooted the modem and waited 30 minutes and then plugged it back in, it might help clear it. IT DID NOT! I'm getting abysmal download speeds of 2 and 3 mb/s. It finally, finally connected to my router and 2 and 3 mb download speeds is what I have. It did not want to connect. This is an expensive disaster and Arris should be ashamed of the absolute inferior quality product they are putting out to the public right now. Absolutely enraged! 🤬 I'll be returning this item. I hope nobody buys this as a used modem.

The ARRIS S33 modem was a great upgrade. My prior modem was another ARRIS product and it worked really well. I've had several ARRIS products and all have functioned without issue. The only reason I upgraded was because my old modem was running DOCSIS 3.0 and I wanted to move to DOCSIS 3.1 to get the most out of the 1.2Gps service that I'm paying for. This new S33 modem improved my speeds across all devices by well over 100Mbps. On my M1 iMac I'm now getting 950 Mbps on average. The ARRIS S33 modem is a five star product. I'll summarize the rest of the story so you don't have to read it if you don't want to. You CAN use this modem with your Xfinity service. But you're going to have to work to get it done. The saga below is provided so if you decide to activate this with Xfinity, you'll have an idea of what you'll go through. Now for the ugly: installing this modem with Xfinity service... This is a simple modem. It's designed to be pretty much plug-n-play. Connect coax, plug in power, plug in ethernet cable then activate through Xfinity's app. All the connections on the modem are simple. I went to Xfinity's app to activate and the activation function wouldn't work. It said I had to contact an Xfinity agent directly. So I started the chat with an Xfinity agent. I spent over an hour chatting with the agent as they tried to figure it out. First they said the modem isn't compatible with Xfinity's service. I pointed out it's the recommended modem on Xfinity's website. Then they said they couldn't find the modem in their system so couldn't register it on my account. More haggling. They escalated the issue. Escalation agent had the same problems. After more than an hour they told me I'd have to take the modem to a service center because "the service centers have special tools to scan the modem into the system directly." He assured me no appointment was necessary with my case number. Off to the Xfinity service center I go. I get there and it's a 45 minute wait. The guy says their case number doesn't mean anything to them and I'd still have to wait in line. The guy calls my name and I walk up to the counter. As soon as I lay the modem box on the counter the guy says, "Oh, no. Another one of these." He proceeds to tell me he'll do everything he can to help but they've not been able to do anything with these modems in the service center. He says the service centers don't have any special tools and have to do the same things the online agents do. And he comments that he wishes the online agents wouldn't tell customers what the service centers can do, they're always wrong and just dump problems on the service center. Sure enough, the modem isn't listed in his system either. Nice guy and admits this situation has been causing a terrible customer experience with several customers. He escalates the case to some tech group offsite. He gives me a new case number and says they will have to try to manually configure the modem for my account and I should get a call within an hour. I walked out ticked off and skeptical that I'd get a call or that they'd fix it. 50 minutes later I get a call. A nice guy from the Xfinity tech group tells me he's got it configured and it should install fine. Just have to activate it through the app. I reinstall the modem and go to the Xfinity app to activate. Same error in the app as before and it makes me contact an agent. So I start the chat and explain the situation. The chat agent says to give him a few minutes to review and attempt the activation. He comes back on about 5 minutes later and says it's activated. Sure enough. The modem light is blue and I once again have data flowing. It took somewhere about 4 hours, two chat sessions, a trip to the local service center and referral to some higher Xfinity tech group; but it finally got installed.

TLDR: ARRIS S33 modem: significant speed upgrade, perfect for 1.2Gbps service, but challenging Xfinity installation. 💻🚀🔄 Upgrading to the ARRIS S33 modem was like jumping to lightspeed in my home network. Coming from a history of using ARRIS products, which have always been stellar, this move was more about staying ahead in the internet speed game. The motivation? To tap into the full potential of my 1.2Gbps service. The previous modem was a faithful servant in the realm of DOCSIS 3.0, but the S33, with its DOCSIS 3.1 technology, has taken things to the next level. It's like unleashing the full power of my internet service. On my M1 iMac, I'm now hitting an average of 950 Mbps, which is phenomenal. It's a five-star experience in terms of performance. However, it's not all smooth sailing. If you're with Xfinity, brace yourself for a bit of an odyssey. The modem itself is designed for simplicity – a plug-n-play dream. But the activation with Xfinity? That's where the plot thickens. My attempt to activate through the Xfinity app hit a wall. The app was a no-go, and the chat with Xfinity agents turned into a marathon of confusion and miscommunication. From compatibility doubts to system non-recognition, it was a series of hurdles. The escalation didn't smooth things out either. A trip to the Xfinity service center, based on agent advice, turned into a waiting game and a revelation that the service centers are just as much in the dark. Despite the assurances and escalations, the solution still felt elusive. But, in a twist worthy of a tech thriller, a call from Xfinity's tech group brought the light at the end of the tunnel. The modem was finally configured, activated, and ready to go. The ordeal? Roughly 4 hours, multiple chats, a service center visit, and a pinch of patience. In conclusion, the ARRIS S33 modem is a beast in terms of speed and reliability, a definite upgrade for anyone looking to maximize their internet service. Just be prepared for a bit of an installation saga with Xfinity – it's worth it in the end!

I'm used to decades of big & bulky modems of old, so I was surprised at how tiny this was when it arrived. Physical setup was simple, as this only only has a single RF connector and two Ethernet ports. The included directions were easy to follow, as far as getting to the interface and setting things up in there. I was unable to activate it via Comcast's activation page. That now redirects you to use the app, which repeatedly refused to accept the MAC address. I ended up getting on chat with Comcast support, and was able to get it activated after about a half an hour of back and forth text messages and emails to verify account ownership, and confirming the "order" for activation. I blame all of that lost time and effort squarely on Comcast, because activation used to be a very easy, self-guided process. Routing through the app, which apparently doesn't have a current list of approved modem MAC addresses, was apparently added in the past year or so. Back to the modem itself. Did I mention that it's tiny? It's been chugging along for several weeks now, without any issues, once I was able to finally activate it. I did end up buying a hub in order to expand the number of Ethernet ports for some legacy equipment we're still using, and a PS4 on which the WiFi stopped working. My only real gripe is the price, considering it's a single-purpose device. Yes, there's a premium on it because it's DOCSIS 3.1-compliant, but that's not exactly new technology now. $99.99 seems more reasonable. On the plus side though, I no longer have to shell out $13 a month to rent Comcast's ancient TG1682G, which I wasn't using the WiFi on anyway.

I've used this modem for just under three months now. It's been fairly solid. I don't have any real complaints that would make me not recommend it. For a couple days I was only getting around 150 Mbps and couldn't figure it out for the life of me. Eventually plugged directly into the modem and did a speed test and finally got the speeds I was expecting. Turns out I didn't update my quality of service settings on my router. The router was acting as a bottleneck. Once I ran another speed test with the router and updated the QoS, I got the full bandwidth I was expecting. Pros: It's fast and as seamless as any other Arris or Motorola. I have 1 Gbps service and it's gotten very close with the various speed tests. I'm assuming that's a combination of advertised vs. actual speeds from my ISP and I don't suspect it's the modem. This should last me until the modem itself fails. Even streaming several devices simultaneously at 4K wouldn't crack 1 Gbps. Heck, even if we get 8K in the future, this thing could take several devices at once. The one benefit I see to having >1 Gbps is for file transfers if you work from home and work with massive files. Even downloading 50-100 GB files via cloud servers hasn't come close to Gbit speeds. Cons: For some reason, internal pings to the modem are now being blocked. Maybe they were always blocked but I could have sworn they weren't. That's a new one for me. This is an incredibly minor downside, but as advertised, only one ethernet port is 2.5 Gbps. Fine. I don't see how anyone in normal use cases would need more than that. This is the modem, not a router or switch. I do wish there was a way to send a reboot signal from within the network, but there are probably security or other issues with that. I think the first router I owned had that. Would be kind of useful, but barely worth mentioning. Other: It claims it has an app. I have almost zero idea why it would need one. Overall: Hopefully this is the last modem I buy. Seems likely. Would recommend. Edit: Cleaned up units.

Installed this to replace an old DOCSIS 3.0 Arris unit that I thought was "future-proof" when I got it several years ago. Time and DOCSIS standards keep marching on, however... Pros: Fast, mostly simple install (once you activate it - see below), resilient performance. Cons: Ridiculous organic shape, arcane management tools that can be intimidating to some, ISP activation booby trap. Spectrum upgraded us to 1GB service involuntarily, so most of my downstream equipment needed to be upgraded (DOCSIS 3.1, WiFi 6) to take advantage of the full bandwidth. Since I was getting annoyed with my older Linksys router equipment, it was not a hard sell, or a significant cash outlay for a WFH household. I chose this model (as opposed to slightly cheaper Arris units) for the 2.5G ethernet output. Hooking everything up is easy enough, but if you are thinking of powering down the network and replacing the router, access points, and modem all at the same time - DO NOT. First and foremost, you need to be able to get on the network to set up the modem. If you are on Spectrum cable, you may also need to log into your account and give them the MAC address for the modem so they can provision it. I ONLY log into that account when I set up new equipment like this, so it is so infrequent I forgot to do it. In hindsight - do the modem first using your old WiFi, get the modem working right, and THEN knock yourself out replacing and tinkering with routers. The biggest "con" based on Arris' choices is the ridiculous curvy design. It won't lay on its side, or any other surface except its base, which is an odd choice for something that has no antenna or broadcast range constraints. The "bottle of fancy shampoo" design aesthetic is cool for things people carry around, but for something that sits on a shelf and is part of a network setup - why not just make it a boxy, stackable, wall-mountable shape??? Anyway, once activated, and provided you are okay with the form factor of the thing, it performs well. No complaints so far. Plays well with my TP-Link setup, though I have no way of knowing if the ethernet interlink is 1G or 2.5G, so until my ISP cranks up the speed again, I am set for now.