X201 problems with Centrino 6300 network card.

[Orange245]

Hello!

My girlfriend has a X201 Type 3680-k84s/n laptop with a Intel Centrino Ultimate AGN 6300 wifi-card. The problem occurs when the laptop have been sleeping and it could take 5 minutes to connect with the wifi card even if 802.11-radio is on when Fn+F5 is pressed (access connections). And sometimes it just loses its connection without beeing slept down. I do not know what to do. When it is active, it has a good signal strength.

Should I replace the network card or should I try any settings first? I have tested to upgrade and downgrade the driver several times but it makes no difference.

Any idea how to change this network card if needed?

Thanks in advance
Christoffer