If it's out of warranty and you don't want to spend loads of money reapairing it, your options are limited.
Personally I would check drivers are up to date, at a long shot re-install Windows, otherwise, disable it and use a USB/PCMCIA adaptor. I am guessing nothing has been upgraded/changed internally before this occured?
I have a HP laptop that had a fault with the buit in wireless adaptor, the fix? New mainboard

Thankfully it was under warranty, what this would have cost otherwise I dread to think, probably less then a new laptop I would guess?
Some models have an access hatch to get to the adpaptor, this would allow a new adaptor to be installed without opening the case, have you checked this?
edit: just a thought, have you checked for an avaliable bios update?