DW WLAN network controller using more CPU

Hi

I have got this new Dell inspiron 1521 with windows 8 and I am facing some weird problem with its DW WLAN NETWORK CONTROLLER.

it uses more of cpu resources (as seen from task manager) and causes the active window to become non active.

this makes it frustrating to work, means I am typing some username or anything in IE or Chrome or anywhere else and it suddenly becomes non active window (non selected as if some thing else is selected) and again becomes active in few seconds or I have to click anywhere in the window to make it active.

some times a pop up opens that "DW WLAN NETWORK CONTROLLER HAS STOPPED WORKING" send this information to microsoft.

This happens randomly and I'm not able to figure out when this thing occur, means I'm running on battery or power supply.

I have not used wifi on this laptop and I don't have wifi modem. I always use internet through ethernet cable.

One more thing whenever this problem occurs, I stop all the process related to WLAN in task manager and the problem of active-non active window and popup message disappears.

I have tried to uninstall and install the network adapter. also tried latest drivers from dell website.

somebody please help,

Thank you.