I have a network card , the one mentioned in title on my laptop , and
Vista system, I have no idea why,but this card loses randomly (sometimes for short sometimes for quite long time) a connection with a router as well as main net, I've tried to deal with a problem by changing the configuration but it didn't work
Can somebody help me? or maybe is it possible to change a card for another one?

i had the same problem lg laptop , i googled for weeks & came across many possible remedies but never got lucky until i decided to recover the system using dvd recovery. when done and launched windows i spent 3 hours online without a single disconnect, but after updating the wireless driver the random disconnecting came back , this time i didn't recover the whole system , i roll back driver and its working so good so far.

There is 2 main causes to frequent wifi connection drop. Incorrect security settings, as in the setting is not compatible with your lappy. And as you stated above; drivers. Drivers is a huge cause of this. Also, if you have IPv6 enabled on that interface, please do yourself the headache and disable that rubbish.