Computer freezing when network card ad-hoc wifi enabled.

[hiberNative]

I'm using a network card in my desktop to enable ad-hoc wifi for my iPhone and iPad, but when I enable it, my computer constantly freezes a few seconds at a time while using the wireless connection. Anyone know why that is?

I'm only creating a WEP network since WPA2 doesn't seem to work (getting a confirmed connection, but does not work).

I'm on Win7 and the network card is ASUS PCI-N10 PCI 150 Mbit Wireless