That's strange. Most "new" notebooks have two antennas concted to the WLAN card. This is to give you a beter reception. Nevertheless it should even work only with one antenna connected - you might have a poorer reception, but still it has to work.
But still you say that your Vista doesn't detect the card - this has nothing to do with the antennas!!! The card has to be detected even if no antenna is connected. You have checked the Device manager and it's really not detected, it's not just missing the driver?
Given the fact that you bought a new WLAN card and that even that one is not detected in the OS I'd propose to do the following:
1) download a live linux CD like Ubuntu
burn teh CD and boot from it then choose "Try Ubuntu without any change to your computer"
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2) when the live system will load it should also detect the WLAN card. If it does, clap hands and
3) So now you know that the card works and that means that there is something wrong with your Vista. I'd reccomend a clean install of the operating system (Vista in your case) and it has to work.
2a) if the live os will not detect the wlan card, try it one more time with your old wlan card. If you're still unsucessfull then this means that you most likely have a faulty motherboard.
If it's infact a mb problem, then I'd recomend buying a USB WLAN adapter and work with that. A new mb would definetly be too expensive.
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