Extremely weird WIFI problem (AAone D260)

Hi guys,

I have been running XP on my D260 for a year without any problem. However,after I upgraded to Win 7 ultimate last night everything works except my wireless adapter (Broadcom 802.11n without Bluetooth). I installed the driver from the offical acer website and win 7 can detect the device without any issue. But the wireless cannot detect any router or access point. The most weird thing happened after I flashed the bios (any version), the wifi adapter would work like a champ before the next RESTART. So basically I Hibernate the machine and wake it back up without affecting the WIFI, but as long as I do a RESTART / SHUT DOWN it would go back to square one. I have tried all versions of BIOS and few version of the Broadcom driver but nothing changed. Seems like there is only one guy who had the same problem on notebookreview.com forum. http://forum.notebookreview.com/acer/550057-odd-wireless-adapter-problem-acer-aspire-one-d260.html
I really need your help urgently.

Thanks a lot.

Max