The performance of cable is highly dependant on what those who live near you (in tech. terms, the people on the same headend as you) do. This is because, as with the TV you get on that cable, it's a broadcast medium and your cable modem filters out what isn't yours. DSL does not have this property and can be considered more stable. Some phone wiring is old and crappy though, and DSL will either flat-out not work, or work poorly. I don't know what the situation is in your area but typically the telco will only guarantee your phone line's quality to a level well short of what you need for DSL. Check with your neighbours, if they have DSL, if they had any problems getting it, especially if their houses are a similar age to yours.

As for speed, cable has been much faster than DSL in the past, but new developments such as ADSL2+ are closing that gap, offering a theoretical maximum of 24Mbps.

I would talk to people in your area, and check out what speeds and what plans are available in your area. All other things being equivalent (or close enough considering what you intend to do on the Internet), I would take DSL over cable.

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