Just getting 25% of my gigabit Comcast internet speed? That's a huge waste of money!
Just getting 25% of my gigabit Comcast internet speed? That's a huge waste of money!
I have a Comcast gigabit internet plan, but I never get that fast speed. I use my own Motorola DCSIS 3.0 modem and an Asus RT-AC68R/U router running TomatoUSB custom software on my ethernet cable to the PC in my office. The down speed is always around 240 Mbps while the up speed stays steady at about 24 Mbps. When I connect my phone or other devices via WiFi, they usually get half of that speed. This is really frustrating because I pay for 1000 mbps but only get 25% of it. I tried connecting the laptop straight to the modem and bypassing the router to see if that helped; even then, I was limited to about 500 Mbps. If I plugged the laptop directly into the router instead, speeds dropped back down to the usual 240-280 Mbps. I know Docsis 3.1 is needed for 1 gigabit, but Docsis 3.0 should give me up to 900 mbps. I recently bought a new Nighthawk wifi6 cable modem router combo from Costco because my old setup was slowing everything down. My surprise? The speeds stayed exactly the same even though the new router supports Docsis 3.1. I ended up throwing it all back in the box after trying it for a few days since it had no real benefits and caused too many connection drops. I don't think that router helped me at all because of these issues. If anyone has any tips or advice on why my speeds are so slow, please let me know.
Check your contract with your internet provider again. Just like a lot of people assume, it probably says "up to 1000 Mbps." It likely means more than just "at least" or "always," so you could be getting less than that depending on how often you use the internet. There might even be words in there about what your average speed is.
I don't know why connecting directly to the modem isn't working better. It feels like the ISP set up their account wrong if you only get 500mbps. Your issue with 240mbps is probably because the router uses Tomato firmware. Modern routers use hardware NAT offload, which means they don't have to work too hard on CPU tasks. However, using third-party firmware can cause license problems, forcing the CPU chip to do all the NATing itself instead of the hardware. You might not even reach 300mbps on the best router models. I think you could still try installing Merlin images for that router. Merlin is a bit simpler than other third-party options but it includes many features. The important thing is they work with Asus routers and use the Asus NAT acceleration drivers.
I have not been impressed with Netgear products recently. My friend had a Netgear modem and router. Both said they could give gigabit speeds, but he couldn't get them when using the combo. He switched to Motorola, and that fixed his problem. We both thought it was strange because we couldn't hit gigabit speed with a Netgear-Netgear setup. I have not recommended any Netgear stuff in years except for a cheap $15 unmanaged switch. Their software team isn't very good anymore. Comcast has profiles for all their approved modems, but they failed to provision my Docsis 3.0 modem for gigabit speeds; the best speed we got was only 300mbps. I bought a Motorola MB8600 Dociss 3.1 modem and it solved the issue with instant gigabit speeds. They also have an MB8611 now, which actually has a real 2.5gbe port. You should not run Tomato firmware on routers anymore; it is no longer updated, so security is a big problem. As BILLG mentioned earlier, get MERLIN firmware for Asus routers instead. Merlin takes the published Asus firmware and brings in newer OpenWRT libraries. This makes everything up to date and much more reliable, plus it has hardware NAT.
The cable modem is a Motorola MB7621 that supports 24 channels and has an HMM... I was actually getting the same fast speeds with my old Asus/T-Mobile firmware before I tried installing the custom Tomato firmware. Also, since I only have internet from Comcast, the signal goes straight from the street into the smart box in our house closet, then directly to the modem. There are no splitters or other devices blocking the signal coming into the modem. Thanks a lot for your help!
Motorola's website says that the speed on their modem is just right for Comcast's plans, but I don't think they will put a profile out there that gets all the power out of it. The modem might be able to handle 24 lanes, but Comcast probably won't give you those 24—they could only give you 12 or less. If you have a gigabit plan, I'd upgrade to a DOCSIS 3.1 Modem instead.
I'm not a fan of combo units. Wifi protocols tend to update way faster than cable ones. Docsis 3.1 can go up to 10gbps, so we'll stick with that for now. While people are still switching to wifi 6E and they're already launching wifi 7 by the end of this year, wifi 7 will give much more bandwidth with a 320mhz channel width. It's supposed to help use vr googles without wires at full resolution. For a modem, I'd suggest Motorola MB8600 or MB8611. They've been solid for everyone I've recommended them to. I've used the MB8600 for years and it hasn't missed a beat. I don't know how good or bad their combo unit is.
If you have a DOCSIS 3.0 modem with only 4 or 8 download streams, it might just be fine for up to 500 Mbps sometimes on Comcast's network because that line is oversubscribed. It could go faster during the night. I would strongly suggest getting a DOCSIS 3.1 modem like the MB8600 mentioned earlier with 32 streams. Those have great PIE which means you can get very low ping under load, so "A" bufferbloat scores show up on speedtest sites even without QoS in your router. With some tweaking of cake QoS, you could hit 5 ms and get an "A+" but this needs a lot of CPU power to do in software. Your RT-AC68 has only enough power to run that up to about 93 Mbps. The latest FreshTomato (the current fork of Tomato) from 2023.1 is only three days old, so I guess it's as fresh as possible. It supports NAT acceleration and hardware offloading just like stock firmware as long as you select the CTF and FA options. Just like stock firmware prevents QoS from working properly because some NAT work gets done in the switch chip instead of the CPU, I'd suggest using SmallNetBuilder WAN-to-LAN router charts for routers that can move gigabit speeds without needing QoS. With early firmware your RT-AC68 tested at 754.5 Mbps but note the Netgear R7000 which has the same chipset and all the same hardware except the CPU is clocked to 1000 MHz; it runs full gigabit wire speeds at about 931.4 Mbps. You can overclock your router to 1000 MHz in Tomato using commandline under Tools--System Commands and I have never seen one not run at 1000 MHz (the R7000 is much bigger with a better heatsink so don't put it near heat). Just something to try before buying new hardware. I would also recommend against modem/router combo devices because you cannot flash firmware on the router side of those, so you are stuck with stock—and not even the latest stock but whatever the cable company decides to push to it. You could be stuck with security vulnerabilities while Comcast is happy to stay with an older version to avoid validation hassles. And of course then Comcast broadcasts a free open xfinitywifi Guest Wifi hotspot from your modem to any Comcast subscriber. I don't like buying devices I cannot control.