I found the Netgear CM 400 to be a good buy. Used Motorola SurfBoards (SB) before but they don't seem to last, I guess because they were the cable providers. I had the same trouble with AT&Ts provided DSL modem, didn't last a year and I bought my own.
Actually the Motorola (now Arris) Surfboards can be a great modem with just one mod. Read about it a long time ago on another forum that has since folded. The trouble is that though there's a place in the housing for one, doesn't include a heatsink by default, which for those spending 8-12 hours on their computers per day will often lead to a hot running modem. A couple of members learned of the heatsink option elsewhere, used to be included, that's why the place is there for one. Maybe by now, that's not the case, yet when it was pure Motorola, was so.
One could order the heatsink & install it themselves, extending it's life for years, just like with a CPU install, use a drop of thermal paste, and were better than new.
Kind of coincidental timing, the RCA DCM425 modem, a DOCSIS 2.0 model, suddenly gave up after 6 faithful years of service, brand new out of the box. I was there when the Time Warner tech installed it, and he left the box & documentation behind, so knew that it was new (or 'old new' stock). Plus new items has a new smell or feel & the modem did, unlike the one I received in return below.
Though the one that I returned was in a shrink wrap package, after opening, quickly seen that it wasn't new, in fact didn't spend much effort cleaning up. It's a Ubee model, but with DOCSIS 3.0, downloads holds their speed better than with the older modem, though have doubts that it'll hold up for as long as the RCA. It's well reviewed, yet not in a factory sealed box.
And the reason why I didn't 'qualify' for a brand new one (a Motorola Arris, as the latest Amazon reviewer said that TWC is pushing)? Because I have the EarthLink Internet package, which is plenty fast & costs less than Time Warner's Roadrunner, but that's the key. Rather than me paying the same price year after year with EarthLink (other than modem fee), one had to threaten to cut off service every 12 months to 'negotiate' a deal that'll keep pricing the same, yet they'll still try to up it $10 or so. All one has to do is get a quote from AT&T, tell them you're cutting service off on a certain date, within hours, one of their 'retention center' staff members will give an outstanding deal. Yet may or may not tell one it's for 12 months only, and the last one was the end for me with TWC.
But guess what? EarthLink buys & resells service through local ISP's (the BrightHouse network), so my bill & service still comes from Time Warner. And the speeds has never been greater since I made the switch in 2010. Only difference is that I'm a TWC customer in billing & service only, don't get the perks like wireless hotspots & WiMax connections, that's otherwise no charge to their Standard or higher subscribers.
And while I may be getting the runaround, for the first 4 years, EarthLink absorbed the modem rental fee, but it got so high that they couldn't. What I'm being told is that I have to contact EarthLink about modems, and they in turn tell me that it's up to the local ISP. Should I have to go one again with the modem (or modem/router combo) dance, like the first year to 18 months I lived here, before the new RCA in 2010, went through 4 total, two of which was brand new Netgear modem/router combos. The last one that was brought out looked as though pulled from the trash can, and performed as such. On the last call during that stretch, I met the tech coming out of the van & asked for a modem only, and he obliged, with the RCA that until this past Sunday, ran great. I purchased my own router, and have upgraded that component 3 times, though only one 'went out' on me, the rest were upgrades.
So please do your homework, Queen-Evie provided the approved list for your tier, check out reviews for modem before pulling the trigger. Newegg also carries these, I've seen the Motorola Arris 6141 model for as low as $59.99 on promo, and a free USB wireless card was included. Sometimes it'll be $10 more & a free router tossed in, usually a TP-Link model. Here's links for both the 6121 & 6141 models on Amazon. The 6121 is well reviewed by over 10,000 customers, not to count at least that many more who didn't bother writing one & at the moment, $35 higher on Newegg.
Should I have to go through the merry-go-round of modems with TWC, will get to the bottom of my rights for a new modem of my choice, even if I have to contact the FTC, though will give them the chance by letting them know my intentions first. Usually once they know the customer knows who to contact for rights, they'll furnish the list. And if it's the Ubee for my service level, that's fine by me, as long as this one continues to run as it has, and furthermore, it's truly new as described. Like Queen-Evie was saying, don't bother with purchasing used/refurbished modems & you should be OK.
One last thing & I'm out, combo modem/routers tends to run hotter than a standalone of each, sometimes very much so. The problem will show & fast, if downloading a huge Linux ISO, it'll heat up & speeds will come to a crawl, even with a download manager. Continual usage of this type will burn these units up, so I cannot in good faith recommend this type of purchase, no matter how sweet the deal may be. That's why most consumers has separate units, especially those with cable based ISP's. AT&T U-verse customers may have less of a choice, or at least in this area. A close relative has their combo router/modem & it runs good, feeds strong signal to two Roku devices as well as two smart TV's & 3 computers & is only warm to the touch, which is fantastic, considering all of the connected devices. The bad is they can't get into the interface to change the password, it's just 8 numbers. I advised her to call Customer Service & ask to choose her own unique one. Or get the modem's model number & download the manual for the information that may be helpful. I doubt that AT&T would object to a password change for WPA2-PSK access, but may have to leave the rest alone.
Had it been me, I'd had demanded it through the tech during setup, I guess she wasn't thinking........
Yet the speed is great, and there's always two users online, I ran a speedtest & still came up with over 30Mbps down & 5Mbps up while one was viewing content through Roku & the other had two browsers open with several pages on each & connected to Skype also.
Edited by cat1092, 11 March 2016 - 04:18 AM.