My laptop specs are 8GB Ram, intel core i7 2620M, 128GB SSD .As the inbuilt wifi card is causing a lot of audio latency issues, all my youtube videos are lagging in audio therefore i'm currently using a USB Wifi adapter to fix this problem. Due to limited no of USB ports . i would like to know whether i can upgrade the existing wifi card to a newer wifi card as the driver support for the inbuilt wifi card is not present anymore.
Sure, it looks like it uses PCIe half mini cards. A replacement would need to be one of those. You'll also want the same number of antenna leads. For instance if your laptop is only has one antenna lead going to your card a card with two antenna connectors won't work.
Although I haven't tried it. From what I've read you can upgrade the internal card of an 802.11n laptop to 802.11ac.