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Baisically, the original Airport card works using an older version of wireless technonlogy (802.11b). This means that the transfer speed (11Mbps) is slower than the current standard (802.11g - 54Mbps) and the network security encryption is not as advanced. However, this should not prevent these two types from talking to each other though you will only get data transfer at 11Mbps - which is adequate for most home internet use.

Google came up with this.
 
That i will have to check when i get home, as i am at work at the moment, and it was my dad that set up his pc internet.
Thanks
 
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