wlan wireless card

Your card IS perfectly compatable, the Dell tech is partially incorrect.

If have a "N" class access point, any class adapter will work just fine. However, the access point will automatically "drop down" to the lower rate when a "less than N" adapter connects to the wlan. That means that if your comp has a G adapter then the entire wlan will run at G rates rather than N rates.

But all this has nothing at all to do w/ your COX connection. Your COX connection is a far lower rate than ANY wifi adapter.

Also, realize that NO wifi adapter will get the actual rates they are capable of. So, if have a G adapter, you can connect at 54 mbps, but the actual rate will be somewhere around 30 mbps max due to "overhead" and other technical reasons. Same goes for N. The rule of thumb is to expect approx 1/2 the potential rate.

COX max rate is less than 10 mbps, thus your wifi adapter far exceeds the available throughput of COX.

The wifi adapter rates, in practical use, apply ONLY to networked computers on YOUR network, not the Internet If transfer files over your local network, they will travel at approx 1/2 the "connection rate" of the wifi adapter, which is still about 5 times faster than download rates from COX.