I currently have the 50mbs service and am using a Scientific Atlanta DSAC210 modem. In the last few weeks/months I have consistently have had my internet speed drop and come back. It happens just about every day and at seemingly random times of the day. Has anyone had the same issue? I know this modem is a bit old and was wondering if upgrading would make a difference?
AFAIK, the DSAC210 is a DOCSIS 2 modem only capable of a theoretical max speed of 42Mbps, in practice you won't get near that. You won't come close to the 50Mbps you are paying for. Upgrading should definitely make a difference, upgrade to at least an 8x4 channel DOCSIS 3 modem, see Cox approved list here.
Do you have a router attached? If so, what one? If you are running something like the Linksys WRT54g, a great router in it's day, that's a bottleneck too. I would recommend a router with gigabit Ethernet ports, dual WiFi band and 802.11ac support. TP-Link makes a few at the $50-90 price point and ASUS & Netgear make higher end routers.
If you are using a DSAC210 you are going to be limited to a max of 25Mbps or so as it's a DOCSIS 2.0 modem. Plus, it won't have the reliability of current generation modem.
DOCSIS 2.0 modems have 1 channel for sending, and 1 for receiving. If there is any interference or signal issues, there is nothing for it to fall-back on.
DOCSIS 3.0 modems have a minimum of 4 channels for sending and 4 for receiving. This allows faster connections, more error resistant connections, and fallback options.
(~25Mbps of real-world bandwidth capability per channel)
As @AllenP stated, an upgrade of modem would be highly recommended, as well as an upgrade in router. You can save some money in the short-term by just stopping by a Cox retail outlet and rent a modem to see about any improvements, then make your decision to purchase either from Cox or from Amazon/BestBuy/etc or keep renting.
